From embedded-pv-devel-bounces@lists.xenproject.org Wed Mar 04 17:31:34 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Wed, 04 Mar 2015 17:31:34 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTD8w-0003tz-Bq; Wed, 04 Mar 2015 17:31:34 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTD8u-0003o2-HX; Wed, 04 Mar 2015 17:31:32 +0000 Received: from [85.158.137.68] by server-14.bemta-3.messagelabs.com id 73/CE-02885-37147F45; Wed, 04 Mar 2015 17:31:31 +0000 X-Env-Sender: lars.kurth.xen@gmail.com X-Msg-Ref: server-9.tower-31.messagelabs.com!1425490288!9366651!1 X-Originating-IP: [74.125.82.182] X-SpamReason: No, hits=0.1 required=7.0 tests=HTML_50_60,HTML_MESSAGE X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 17322 invoked from network); 4 Mar 2015 17:31:28 -0000 Received: from mail-we0-f182.google.com (HELO mail-we0-f182.google.com) (74.125.82.182) by server-9.tower-31.messagelabs.com with RC4-SHA encrypted SMTP; 4 Mar 2015 17:31:28 -0000 Received: by wesq59 with SMTP id q59so47892021wes.1; Wed, 04 Mar 2015 09:31:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:content-type:subject:date:message-id:cc:to:mime-version; bh=t49/7hxrjK3pwdvsWyfwKkQOQhHjgOx1RsyUHkYerd0=; b=pZ5uJKTpYbrRwLCYZ9PZON1pGrtqKdCVCHw7Lxg4AXMks1+42C2dZ+Xl5Ez4LOWptL 1JdUx+Cw4sT063tHymI4WkyHA7ECgAZ10LxnCCxySy6Ez6TaON2SWsULakWcnyddZzKy 4TFMuSk/SMqCIzWpeTCCCkaIKC5leQMIbxRKULFvvWHW34O+Y3Xr20mjSUL9AraaX3u3 ZBcnPJkyNjL3h9fSSpDRpS9l/0nEnNQcatwlQPttZwjvgLGgsxHnftW74mwqp1HKH2h0 THzI2Cj+B3ey3nx5iMhY0KX4iP42416jK+ThVz47KPhFf8gKa9Hu+P5/TRigzKreM0vm i0Qg== X-Received: by 10.194.205.138 with SMTP id lg10mr9870324wjc.130.1425490288129; Wed, 04 Mar 2015 09:31:28 -0800 (PST) Received: from [192.168.0.8] (97e3cd44.skybroadband.com. [151.227.205.68]) by mx.google.com with ESMTPSA id gf11sm7995380wic.18.2015.03.04.09.31.23 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 04 Mar 2015 09:31:26 -0800 (PST) From: Lars Kurth Date: Wed, 4 Mar 2015 17:31:18 +0000 Message-Id: <44A7E990-9056-405D-B619-6695B2204E33@gmail.com> To: xen-devel , xen-api@lists.xenproject.org, mirageos-devel , embedded-pv-devel@lists.xenproject.org Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) X-Mailer: Apple Mail (2.2070.6) Cc: advisory-board@lists.xenproject.org, Russ Pavlicek Subject: [Embedded-pv-devel] GSoC 2015 - Not accepted ... but some mentoring organisations which have several Xen related projects in them are X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============0052809818460878178==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============0052809818460878178== Content-Type: multipart/alternative; boundary="Apple-Mail=_AE147FE4-C337-4AA2-BAB2-AE4136222F15" --Apple-Mail=_AE147FE4-C337-4AA2-BAB2-AE4136222F15 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 Hi folks, just a quick note to let you know that we were not accepted for GSoC = this year. Do note that the Linux Foundation, OpenStack Foundation and = many of the other usual suspects have not been accepted this year. We = will find out more why on Friday. However, there are at least 4 Xen = related projects that are managed by other =20 I made a note at the top of = http://wiki.xenproject.org/wiki/Archived/GSoC_2015 = to point applicants = to some of those projects. I have found 5 so far (which may bot be a = complete list): Xen based Hypervisor in a Box @ Centos=C2=A0 = Xen guest support for OpenBSD @ Open BSD Foundation=C2=A0 = 3 Xen related projects @ Ganeti = Other projects which were accepted are QEMU = : note = that there are no Xen related projects, but given that Xen has good = relationships with the QEMU community we may be able to get one or two = projects onto the list if someone steps up and is willing to mentor Best Regards Lars= --Apple-Mail=_AE147FE4-C337-4AA2-BAB2-AE4136222F15 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=us-ascii Hi folks,

just = a quick note to let you know that we were not accepted for GSoC this = year. Do note that the Linux Foundation, OpenStack Foundation and many = of the other usual suspects have not been accepted this year. We will = find out more why on Friday. However, there are at least 4 Xen related = projects that are managed by other
 
I made a note at the top of http://wiki.xenproject.org/wiki/Archived/GSoC_2015 to = point applicants to some of those projects. I have found 5 so far (which = may bot be a complete list):
Other projects which were accepted are QEMU: note that there are no Xen related projects, but = given that Xen has good relationships with the QEMU community we may be = able to get one or two projects onto the list if someone steps up and is = willing to mentor

Best Regards
Lars
= --Apple-Mail=_AE147FE4-C337-4AA2-BAB2-AE4136222F15-- --===============0052809818460878178== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============0052809818460878178==-- From embedded-pv-devel-bounces@lists.xenproject.org Wed Mar 04 17:31:34 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Wed, 04 Mar 2015 17:31:34 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTD8w-0003tz-Bq; Wed, 04 Mar 2015 17:31:34 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTD8u-0003o2-HX; Wed, 04 Mar 2015 17:31:32 +0000 Received: from [85.158.137.68] by server-14.bemta-3.messagelabs.com id 73/CE-02885-37147F45; Wed, 04 Mar 2015 17:31:31 +0000 X-Env-Sender: lars.kurth.xen@gmail.com X-Msg-Ref: server-9.tower-31.messagelabs.com!1425490288!9366651!1 X-Originating-IP: [74.125.82.182] X-SpamReason: No, hits=0.1 required=7.0 tests=HTML_50_60,HTML_MESSAGE X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 17322 invoked from network); 4 Mar 2015 17:31:28 -0000 Received: from mail-we0-f182.google.com (HELO mail-we0-f182.google.com) (74.125.82.182) by server-9.tower-31.messagelabs.com with RC4-SHA encrypted SMTP; 4 Mar 2015 17:31:28 -0000 Received: by wesq59 with SMTP id q59so47892021wes.1; Wed, 04 Mar 2015 09:31:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:content-type:subject:date:message-id:cc:to:mime-version; bh=t49/7hxrjK3pwdvsWyfwKkQOQhHjgOx1RsyUHkYerd0=; b=pZ5uJKTpYbrRwLCYZ9PZON1pGrtqKdCVCHw7Lxg4AXMks1+42C2dZ+Xl5Ez4LOWptL 1JdUx+Cw4sT063tHymI4WkyHA7ECgAZ10LxnCCxySy6Ez6TaON2SWsULakWcnyddZzKy 4TFMuSk/SMqCIzWpeTCCCkaIKC5leQMIbxRKULFvvWHW34O+Y3Xr20mjSUL9AraaX3u3 ZBcnPJkyNjL3h9fSSpDRpS9l/0nEnNQcatwlQPttZwjvgLGgsxHnftW74mwqp1HKH2h0 THzI2Cj+B3ey3nx5iMhY0KX4iP42416jK+ThVz47KPhFf8gKa9Hu+P5/TRigzKreM0vm i0Qg== X-Received: by 10.194.205.138 with SMTP id lg10mr9870324wjc.130.1425490288129; Wed, 04 Mar 2015 09:31:28 -0800 (PST) Received: from [192.168.0.8] (97e3cd44.skybroadband.com. [151.227.205.68]) by mx.google.com with ESMTPSA id gf11sm7995380wic.18.2015.03.04.09.31.23 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 04 Mar 2015 09:31:26 -0800 (PST) From: Lars Kurth Date: Wed, 4 Mar 2015 17:31:18 +0000 Message-Id: <44A7E990-9056-405D-B619-6695B2204E33@gmail.com> To: xen-devel , xen-api@lists.xenproject.org, mirageos-devel , embedded-pv-devel@lists.xenproject.org Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) X-Mailer: Apple Mail (2.2070.6) Cc: advisory-board@lists.xenproject.org, Russ Pavlicek Subject: [Embedded-pv-devel] GSoC 2015 - Not accepted ... but some mentoring organisations which have several Xen related projects in them are X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============0052809818460878178==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============0052809818460878178== Content-Type: multipart/alternative; boundary="Apple-Mail=_AE147FE4-C337-4AA2-BAB2-AE4136222F15" --Apple-Mail=_AE147FE4-C337-4AA2-BAB2-AE4136222F15 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 Hi folks, just a quick note to let you know that we were not accepted for GSoC = this year. Do note that the Linux Foundation, OpenStack Foundation and = many of the other usual suspects have not been accepted this year. We = will find out more why on Friday. However, there are at least 4 Xen = related projects that are managed by other =20 I made a note at the top of = http://wiki.xenproject.org/wiki/Archived/GSoC_2015 = to point applicants = to some of those projects. I have found 5 so far (which may bot be a = complete list): Xen based Hypervisor in a Box @ Centos=C2=A0 = Xen guest support for OpenBSD @ Open BSD Foundation=C2=A0 = 3 Xen related projects @ Ganeti = Other projects which were accepted are QEMU = : note = that there are no Xen related projects, but given that Xen has good = relationships with the QEMU community we may be able to get one or two = projects onto the list if someone steps up and is willing to mentor Best Regards Lars= --Apple-Mail=_AE147FE4-C337-4AA2-BAB2-AE4136222F15 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=us-ascii Hi folks,

just = a quick note to let you know that we were not accepted for GSoC this = year. Do note that the Linux Foundation, OpenStack Foundation and many = of the other usual suspects have not been accepted this year. We will = find out more why on Friday. However, there are at least 4 Xen related = projects that are managed by other
 
I made a note at the top of http://wiki.xenproject.org/wiki/Archived/GSoC_2015 to = point applicants to some of those projects. I have found 5 so far (which = may bot be a complete list):
Other projects which were accepted are QEMU: note that there are no Xen related projects, but = given that Xen has good relationships with the QEMU community we may be = able to get one or two projects onto the list if someone steps up and is = willing to mentor

Best Regards
Lars
= --Apple-Mail=_AE147FE4-C337-4AA2-BAB2-AE4136222F15-- --===============0052809818460878178== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============0052809818460878178==-- From embedded-pv-devel-bounces@lists.xenproject.org Wed Mar 04 17:40:40 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Wed, 04 Mar 2015 17:40:40 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTDHj-0004wN-Nx; Wed, 04 Mar 2015 17:40:39 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTDHi-0004w5-Pl; Wed, 04 Mar 2015 17:40:38 +0000 Received: from [85.158.137.68] by server-4.bemta-3.messagelabs.com id 9A/8A-03185-59347F45; Wed, 04 Mar 2015 17:40:37 +0000 X-Env-Sender: amc79@cam.ac.uk X-Msg-Ref: server-3.tower-31.messagelabs.com!1425490836!13161956!1 X-Originating-IP: [131.111.8.151] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogMTMxLjExMS44LjE1MSA9PiAxNDE4OTU=\n X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 30335 invoked from network); 4 Mar 2015 17:40:37 -0000 Received: from ppsw-51.csi.cam.ac.uk (HELO ppsw-51.csi.cam.ac.uk) (131.111.8.151) by server-3.tower-31.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 4 Mar 2015 17:40:37 -0000 X-Cam-AntiVirus: no malware found X-Cam-ScannerInfo: http://www.cam.ac.uk/cs/email/scanner/ Received: from host81-149-102-120.in-addr.btopenworld.com ([81.149.102.120]:62968 helo=[10.0.0.31]) by ppsw-51.csi.cam.ac.uk (smtp.hermes.cam.ac.uk [131.111.8.157]:587) with esmtpsa (PLAIN:amc79) (TLSv1:AES128-SHA:128) id 1YTDHg-00036d-Wt (Exim 4.82_3-c0e5623) (return-path ); Wed, 04 Mar 2015 17:40:36 +0000 Mime-Version: 1.0 (Mac OS X Mail 6.6 \(1510\)) From: Amir Chaudhry In-Reply-To: <44A7E990-9056-405D-B619-6695B2204E33@gmail.com> Date: Wed, 4 Mar 2015 17:40:31 +0000 Message-Id: References: <44A7E990-9056-405D-B619-6695B2204E33@gmail.com> To: Lars Kurth X-Mailer: Apple Mail (2.1510) Cc: xen-api@lists.xenproject.org, advisory-board@lists.xenproject.org, Russ Pavlicek , embedded-pv-devel@lists.xenproject.org, mirageos-devel , xen-devel Subject: Re: [Embedded-pv-devel] [MirageOS-devel] GSoC 2015 - Not accepted ... but some mentoring organisations which have several Xen related projects in them are X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: quoted-printable Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org I noticed this the other day and had a quick scout around. "Mozilla not accepted for Google Summer of Code 2015" http://blog.queze.net/post/2015/03/03/Mozilla-not-accepted-for-Google-Summe= r-of-Code-2015 "Google=92s program is enormously popular, and over-subscribed, meaning Goo= gle has had to rotate organisation membership" http://news.open-bio.org/news/2015/03/sadly-obf-not-accepted-for-gsoc-2015/ Very unfortunate as we've had interest in the MirageOS projects. I wondere= d about talking to relevant accepted orgs about adding some MirageOS projec= ts but haven't really had a chance to look into this. Best wishes, Amir On 4 Mar 2015, at 17:31, Lars Kurth wrote: > Hi folks, > = > just a quick note to let you know that we were not accepted for GSoC this= year. Do note that the Linux Foundation, OpenStack Foundation and many of = the other usual suspects have not been accepted this year. We will find out= more why on Friday. However, there are at least 4 Xen related projects tha= t are managed by other > = > I made a note at the top of http://wiki.xenproject.org/wiki/Archived/GSoC= _2015 to point applicants to some of those projects. I have found 5 so far = (which may bot be a complete list): > =95 Xen based Hypervisor in a Box @ Centos = > =95 Xen guest support for OpenBSD @ Open BSD Foundation = > =95 3 Xen related projects @ Ganeti > Other projects which were accepted are QEMU: note that there are no Xen r= elated projects, but given that Xen has good relationships with the QEMU co= mmunity we may be able to get one or two projects onto the list if someone = steps up and is willing to mentor > = > Best Regards > Lars > _______________________________________________ > MirageOS-devel mailing list > MirageOS-devel@lists.xenproject.org > http://lists.xenproject.org/cgi-bin/mailman/listinfo/mirageos-devel _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Wed Mar 04 17:40:40 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Wed, 04 Mar 2015 17:40:40 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTDHj-0004wN-Nx; Wed, 04 Mar 2015 17:40:39 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTDHi-0004w5-Pl; Wed, 04 Mar 2015 17:40:38 +0000 Received: from [85.158.137.68] by server-4.bemta-3.messagelabs.com id 9A/8A-03185-59347F45; Wed, 04 Mar 2015 17:40:37 +0000 X-Env-Sender: amc79@cam.ac.uk X-Msg-Ref: server-3.tower-31.messagelabs.com!1425490836!13161956!1 X-Originating-IP: [131.111.8.151] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogMTMxLjExMS44LjE1MSA9PiAxNDE4OTU=\n X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 30335 invoked from network); 4 Mar 2015 17:40:37 -0000 Received: from ppsw-51.csi.cam.ac.uk (HELO ppsw-51.csi.cam.ac.uk) (131.111.8.151) by server-3.tower-31.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 4 Mar 2015 17:40:37 -0000 X-Cam-AntiVirus: no malware found X-Cam-ScannerInfo: http://www.cam.ac.uk/cs/email/scanner/ Received: from host81-149-102-120.in-addr.btopenworld.com ([81.149.102.120]:62968 helo=[10.0.0.31]) by ppsw-51.csi.cam.ac.uk (smtp.hermes.cam.ac.uk [131.111.8.157]:587) with esmtpsa (PLAIN:amc79) (TLSv1:AES128-SHA:128) id 1YTDHg-00036d-Wt (Exim 4.82_3-c0e5623) (return-path ); Wed, 04 Mar 2015 17:40:36 +0000 Mime-Version: 1.0 (Mac OS X Mail 6.6 \(1510\)) From: Amir Chaudhry In-Reply-To: <44A7E990-9056-405D-B619-6695B2204E33@gmail.com> Date: Wed, 4 Mar 2015 17:40:31 +0000 Message-Id: References: <44A7E990-9056-405D-B619-6695B2204E33@gmail.com> To: Lars Kurth X-Mailer: Apple Mail (2.1510) Cc: xen-api@lists.xenproject.org, advisory-board@lists.xenproject.org, Russ Pavlicek , embedded-pv-devel@lists.xenproject.org, mirageos-devel , xen-devel Subject: Re: [Embedded-pv-devel] [MirageOS-devel] GSoC 2015 - Not accepted ... but some mentoring organisations which have several Xen related projects in them are X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: quoted-printable Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org I noticed this the other day and had a quick scout around. "Mozilla not accepted for Google Summer of Code 2015" http://blog.queze.net/post/2015/03/03/Mozilla-not-accepted-for-Google-Summe= r-of-Code-2015 "Google=92s program is enormously popular, and over-subscribed, meaning Goo= gle has had to rotate organisation membership" http://news.open-bio.org/news/2015/03/sadly-obf-not-accepted-for-gsoc-2015/ Very unfortunate as we've had interest in the MirageOS projects. I wondere= d about talking to relevant accepted orgs about adding some MirageOS projec= ts but haven't really had a chance to look into this. Best wishes, Amir On 4 Mar 2015, at 17:31, Lars Kurth wrote: > Hi folks, > = > just a quick note to let you know that we were not accepted for GSoC this= year. Do note that the Linux Foundation, OpenStack Foundation and many of = the other usual suspects have not been accepted this year. We will find out= more why on Friday. However, there are at least 4 Xen related projects tha= t are managed by other > = > I made a note at the top of http://wiki.xenproject.org/wiki/Archived/GSoC= _2015 to point applicants to some of those projects. I have found 5 so far = (which may bot be a complete list): > =95 Xen based Hypervisor in a Box @ Centos = > =95 Xen guest support for OpenBSD @ Open BSD Foundation = > =95 3 Xen related projects @ Ganeti > Other projects which were accepted are QEMU: note that there are no Xen r= elated projects, but given that Xen has good relationships with the QEMU co= mmunity we may be able to get one or two projects onto the list if someone = steps up and is willing to mentor > = > Best Regards > Lars > _______________________________________________ > MirageOS-devel mailing list > MirageOS-devel@lists.xenproject.org > http://lists.xenproject.org/cgi-bin/mailman/listinfo/mirageos-devel _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Wed Mar 04 18:03:49 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Wed, 04 Mar 2015 18:03:49 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTDe9-0000ga-14; Wed, 04 Mar 2015 18:03:49 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTDe8-0000gF-2K; Wed, 04 Mar 2015 18:03:48 +0000 Received: from [193.109.254.147] by server-2.bemta-14.messagelabs.com id 36/05-31919-20947F45; Wed, 04 Mar 2015 18:03:46 +0000 X-Env-Sender: lars.kurth.xen@gmail.com X-Msg-Ref: server-15.tower-27.messagelabs.com!1425492226!14701372!1 X-Originating-IP: [209.85.212.179] X-SpamReason: No, hits=0.3 required=7.0 tests=MAILTO_TO_SPAM_ADDR X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 26186 invoked from network); 4 Mar 2015 18:03:46 -0000 Received: from mail-wi0-f179.google.com (HELO mail-wi0-f179.google.com) (209.85.212.179) by server-15.tower-27.messagelabs.com with RC4-SHA encrypted SMTP; 4 Mar 2015 18:03:46 -0000 Received: by wiwh11 with SMTP id h11so32857730wiw.3; Wed, 04 Mar 2015 10:03:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=IEZd/R06ZDu9+aGfpFDFSp4wdUz0X9PtXEsPh6J4bCA=; b=YlrEz0JWcmXu5fs78lreDA7waEhBSdEcYMcha3RZGlFV+4+w/XLZdnqAKRuEiT/V4/ 4La8MeLZZ1ZPGeWVLyaGj5L2hirGuW0dLBWuzuSeKac5O5mdJClPksPWGLR58O7d/nTr QYR7vMi65Z4Vbn3ly7cTdyRzRgxrOnDQzfND5pqNcUCgJ8v680FtRTOt2u0y5PdhvSOP V15iJEuLCju83qT4Svt49C2h8/qzCKaDTCnP1xIVi47OH3B49uP5AiIliRkeznafyC0V AiITEUWMJYQ/7rngoJuzsuPFyICnW2OBGpT/zHvKjY9u74btoF6cKQ/+iNpW3cZ0RRLp zXBQ== X-Received: by 10.194.122.196 with SMTP id lu4mr10488430wjb.154.1425492225957; Wed, 04 Mar 2015 10:03:45 -0800 (PST) Received: from [192.168.0.8] (97e3cd44.skybroadband.com. [151.227.205.68]) by mx.google.com with ESMTPSA id lx10sm6984496wjb.17.2015.03.04.10.03.44 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 04 Mar 2015 10:03:45 -0800 (PST) Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) From: Lars Kurth In-Reply-To: Date: Wed, 4 Mar 2015 18:03:43 +0000 Message-Id: <1D0B399F-4839-4B68-B8E6-F387D27F5C88@gmail.com> References: <44A7E990-9056-405D-B619-6695B2204E33@gmail.com> To: Amir Chaudhry X-Mailer: Apple Mail (2.2070.6) Cc: xen-api@lists.xenproject.org, advisory-board@lists.xenproject.org, Russ Pavlicek , embedded-pv-devel@lists.xenproject.org, mirageos-devel , xen-devel Subject: Re: [Embedded-pv-devel] [MirageOS-devel] GSoC 2015 - Not accepted ... but some mentoring organisations which have several Xen related projects in them are X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: quoted-printable Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org > On 4 Mar 2015, at 17:40, Amir Chaudhry wrote: > = > I noticed this the other day and had a quick scout around. > = > "Mozilla not accepted for Google Summer of Code 2015" > http://blog.queze.net/post/2015/03/03/Mozilla-not-accepted-for-Google-Sum= mer-of-Code-2015 > = > "Google=92s program is enormously popular, and over-subscribed, meaning G= oogle has had to rotate organisation membership" > http://news.open-bio.org/news/2015/03/sadly-obf-not-accepted-for-gsoc-201= 5/ I am not particularly surprised. The number of projects is growing, so is c= ompetition. = > Very unfortunate as we've had interest in the MirageOS projects. I wonde= red about talking to relevant accepted orgs about adding some MirageOS proj= ects but haven't really had a chance to look into this. Please go ahead. Of course we will again participate in OPW. I am still one= Advisory Board vote short for approval. Regards Lars _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Wed Mar 04 18:03:49 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Wed, 04 Mar 2015 18:03:49 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTDe9-0000ga-14; Wed, 04 Mar 2015 18:03:49 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTDe8-0000gF-2K; Wed, 04 Mar 2015 18:03:48 +0000 Received: from [193.109.254.147] by server-2.bemta-14.messagelabs.com id 36/05-31919-20947F45; Wed, 04 Mar 2015 18:03:46 +0000 X-Env-Sender: lars.kurth.xen@gmail.com X-Msg-Ref: server-15.tower-27.messagelabs.com!1425492226!14701372!1 X-Originating-IP: [209.85.212.179] X-SpamReason: No, hits=0.3 required=7.0 tests=MAILTO_TO_SPAM_ADDR X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 26186 invoked from network); 4 Mar 2015 18:03:46 -0000 Received: from mail-wi0-f179.google.com (HELO mail-wi0-f179.google.com) (209.85.212.179) by server-15.tower-27.messagelabs.com with RC4-SHA encrypted SMTP; 4 Mar 2015 18:03:46 -0000 Received: by wiwh11 with SMTP id h11so32857730wiw.3; Wed, 04 Mar 2015 10:03:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=IEZd/R06ZDu9+aGfpFDFSp4wdUz0X9PtXEsPh6J4bCA=; b=YlrEz0JWcmXu5fs78lreDA7waEhBSdEcYMcha3RZGlFV+4+w/XLZdnqAKRuEiT/V4/ 4La8MeLZZ1ZPGeWVLyaGj5L2hirGuW0dLBWuzuSeKac5O5mdJClPksPWGLR58O7d/nTr QYR7vMi65Z4Vbn3ly7cTdyRzRgxrOnDQzfND5pqNcUCgJ8v680FtRTOt2u0y5PdhvSOP V15iJEuLCju83qT4Svt49C2h8/qzCKaDTCnP1xIVi47OH3B49uP5AiIliRkeznafyC0V AiITEUWMJYQ/7rngoJuzsuPFyICnW2OBGpT/zHvKjY9u74btoF6cKQ/+iNpW3cZ0RRLp zXBQ== X-Received: by 10.194.122.196 with SMTP id lu4mr10488430wjb.154.1425492225957; Wed, 04 Mar 2015 10:03:45 -0800 (PST) Received: from [192.168.0.8] (97e3cd44.skybroadband.com. [151.227.205.68]) by mx.google.com with ESMTPSA id lx10sm6984496wjb.17.2015.03.04.10.03.44 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 04 Mar 2015 10:03:45 -0800 (PST) Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) From: Lars Kurth In-Reply-To: Date: Wed, 4 Mar 2015 18:03:43 +0000 Message-Id: <1D0B399F-4839-4B68-B8E6-F387D27F5C88@gmail.com> References: <44A7E990-9056-405D-B619-6695B2204E33@gmail.com> To: Amir Chaudhry X-Mailer: Apple Mail (2.2070.6) Cc: xen-api@lists.xenproject.org, advisory-board@lists.xenproject.org, Russ Pavlicek , embedded-pv-devel@lists.xenproject.org, mirageos-devel , xen-devel Subject: Re: [Embedded-pv-devel] [MirageOS-devel] GSoC 2015 - Not accepted ... but some mentoring organisations which have several Xen related projects in them are X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: quoted-printable Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org > On 4 Mar 2015, at 17:40, Amir Chaudhry wrote: > = > I noticed this the other day and had a quick scout around. > = > "Mozilla not accepted for Google Summer of Code 2015" > http://blog.queze.net/post/2015/03/03/Mozilla-not-accepted-for-Google-Sum= mer-of-Code-2015 > = > "Google=92s program is enormously popular, and over-subscribed, meaning G= oogle has had to rotate organisation membership" > http://news.open-bio.org/news/2015/03/sadly-obf-not-accepted-for-gsoc-201= 5/ I am not particularly surprised. The number of projects is growing, so is c= ompetition. = > Very unfortunate as we've had interest in the MirageOS projects. I wonde= red about talking to relevant accepted orgs about adding some MirageOS proj= ects but haven't really had a chance to look into this. Please go ahead. Of course we will again participate in OPW. I am still one= Advisory Board vote short for approval. Regards Lars _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 10 15:28:38 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 10 Mar 2015 15:28:38 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YVM5G-0007ZR-Dm; Tue, 10 Mar 2015 15:28:38 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YUr0C-0004LA-Gl for embedded-pv-devel@lists.xenproject.org; Mon, 09 Mar 2015 06:17:20 +0000 Received: from [193.109.254.147] by server-2.bemta-14.messagelabs.com id 80/8C-31919-FEA3DF45; Mon, 09 Mar 2015 06:17:19 +0000 X-Env-Sender: sumadhurakalyan@gmail.com X-Msg-Ref: server-3.tower-27.messagelabs.com!1425881835!15593666!1 X-Originating-IP: [209.85.223.177] X-SpamReason: No, hits=0.4 required=7.0 tests=HTML_50_60,HTML_MESSAGE, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 4262 invoked from network); 9 Mar 2015 06:17:16 -0000 Received: from mail-ie0-f177.google.com (HELO mail-ie0-f177.google.com) (209.85.223.177) by server-3.tower-27.messagelabs.com with RC4-SHA encrypted SMTP; 9 Mar 2015 06:17:16 -0000 Received: by iery20 with SMTP id y20so6988616ier.11 for ; Sun, 08 Mar 2015 23:17:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:from:date:message-id:subject:to:content-type; bh=89LkBbvxpMIgwQ/FFCBO/9jo3bKJfiKMxYDb0+V8gy0=; b=XCqMFmvM0G0P1JPhrHBtRvX09QWvkpmEyX6X4faL89g/8n2j+WtMoyWWrdjwY4HZU5 B/WPFPEUqoB/JLs7NhqJTk2+6PxUnmxUlIdT4jBKF1HhgPNm/0XP+nw248wEZ9H/oU2U k09CJ5i6vs1dECJ1ZrGoS0LJe79eDBW2MtKjC2NbKky0HdEpk8MOB/uKBTYn+rtktNnE jfQXYQ2mRo8sg7kwRV67yta2mrSyPTqBTZiETIUCKij5Jzu7DxaaoCkoxQyCHCVkYNkh 1vjhFtiBrwxB48/GUOivqNbc9oZO9lub0BsJ6/zbob0yBB9dsOiHewYhUVAkL/RFzQxf H+Fw== X-Received: by 10.107.9.88 with SMTP id j85mr33953917ioi.60.1425881835478; Sun, 08 Mar 2015 23:17:15 -0700 (PDT) MIME-Version: 1.0 Received: by 10.107.157.135 with HTTP; Sun, 8 Mar 2015 23:16:55 -0700 (PDT) From: Sumadhura Kalyan Date: Mon, 9 Mar 2015 11:46:55 +0530 Message-ID: To: embedded-pv-devel@lists.xenproject.org X-Mailman-Approved-At: Tue, 10 Mar 2015 15:28:37 +0000 Subject: [Embedded-pv-devel] Android on Xen X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============8405942414333586819==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============8405942414333586819== Content-Type: multipart/alternative; boundary=001a113f8d344ba6320510d4fc13 --001a113f8d344ba6320510d4fc13 Content-Type: text/plain; charset=UTF-8 Hi, I want to install android JB in DomU for xen4.5 Hypervisor,Idon't know what are configuration i have to change.I only did fstab file.and my hardware is exynos5250. Still it not changing any booting up.Is there any thing to configure ,can i know the processes regarding how to boot up the android on xen ARM as guest os. -- *Regards,* *s.kalyan,* *9292050807.* --001a113f8d344ba6320510d4fc13 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable



Hi,
I want to install android JB in DomU= for xen4.5 Hypervisor,Idon't know
what are configur= ation i have to change.I only did fstab file.and my
hard= ware is exynos5250. Still it not changing any booting up.Is there any thing= to configure ,can i know the processes regarding =C2=A0 how to boot up the= android on xen ARM as guest os.



--
Regards,
s.kalyan,
9292050807.
--001a113f8d344ba6320510d4fc13-- --===============8405942414333586819== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============8405942414333586819==-- From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 10 15:28:38 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 10 Mar 2015 15:28:38 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YVM5G-0007ZM-CR; Tue, 10 Mar 2015 15:28:38 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTw7i-0000sZ-I9; Fri, 06 Mar 2015 17:33:18 +0000 Received: from [85.158.139.211] by server-1.bemta-5.messagelabs.com id 13/7B-25903-DD4E9F45; Fri, 06 Mar 2015 17:33:17 +0000 X-Env-Sender: russell.pavlicek@citrix.com X-Msg-Ref: server-3.tower-206.messagelabs.com!1425663193!6048827!1 X-Originating-IP: [66.165.176.63] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni42MyA9PiAzMDYwNDg=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 18886 invoked from network); 6 Mar 2015 17:33:16 -0000 Received: from smtp02.citrix.com (HELO SMTP02.CITRIX.COM) (66.165.176.63) by server-3.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 6 Mar 2015 17:33:16 -0000 X-IronPort-AV: E=Sophos;i="5.11,354,1422921600"; d="scan'208,217";a="242554733" From: Russell Pavlicek To: Lars Kurth , xen-devel , "xen-api@lists.xenproject.org" , mirageos-devel , "embedded-pv-devel@lists.xenproject.org" Thread-Topic: [Xen-devel] GSoC 2015 - Not accepted ... but some mentoring organisations which have several Xen related projects in them are Thread-Index: AQHQWDN0yLBVQRkuaUmt9oendKk+9A== Date: Fri, 6 Mar 2015 17:32:36 +0000 Message-ID: <55E78A57290FB64FA0D3CF672F9F3DA2051B3404@SJCPEX01CL03.citrite.net> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: MIME-Version: 1.0 X-Mailman-Approved-At: Tue, 10 Mar 2015 15:28:37 +0000 Cc: "advisory-board@lists.xenproject.org" Subject: Re: [Embedded-pv-devel] [Xen-devel] GSoC 2015 - Not accepted ... but some mentoring organisations which have several Xen related projects in them are X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============3321188397230113095==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============3321188397230113095== Content-Language: en-US Content-Type: multipart/alternative; boundary="_000_55E78A57290FB64FA0D3CF672F9F3DA2051B3404SJCPEX01CL03cit_" --_000_55E78A57290FB64FA0D3CF672F9F3DA2051B3404SJCPEX01CL03cit_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I reached out to the GSoC people to get information on why we were not acce= pted. The response is not surprising: Carol writes: "We had to make a lot of hard decisions with our GSoC organizations this ye= ar, and unfortunately yours was one of them. We focused a lot on trying to = make space and accept new, small organizations who have never participated = before, and we felt it wouldn't be an extreme hardship for your organizatio= n to take a year off from the program. I hope you all will apply again in a= future year, and good luck with everything this year!" Russ Pavlicek Xen Project Evangelist, Citrix Systems Home Office: +1-301-829-5327 Mobile: +1-301-814-1143 UK VoIP: +44 1223 852 894 ________________________________ From: xen-devel-bounces@lists.xen.org [xen-devel-bounces@lists.xen.org] on = behalf of Lars Kurth [lars.kurth.xen@gmail.com] Sent: Wednesday, March 04, 2015 12:31 PM To: xen-devel; xen-api@lists.xenproject.org; mirageos-devel; embedded-pv-de= vel@lists.xenproject.org Cc: advisory-board@lists.xenproject.org; Russ Pavlicek Subject: [Xen-devel] GSoC 2015 - Not accepted ... but some mentoring organi= sations which have several Xen related projects in them are Hi folks, just a quick note to let you know that we were not accepted for GSoC this y= ear. Do note that the Linux Foundation, OpenStack Foundation and many of th= e other usual suspects have not been accepted this year. We will find out m= ore why on Friday. However, there are at least 4 Xen related projects that = are managed by other I made a note at the top of http://wiki.xenproject.org/wiki/Archived/GSoC_2= 015 to point applicants to some of those projects. I have found 5 so far (w= hich may bot be a complete list): * Xen based Hypervisor in a Box @ Centos * Xen guest support for OpenBSD @ Open BSD Foundation * 3 Xen related projects @ Ganeti Other projects which were accepted are QEMU: note that there are no Xen related project= s, but given that Xen has good relationships with the QEMU community we may= be able to get one or two projects onto the list if someone steps up and i= s willing to mentor Best Regards Lars --_000_55E78A57290FB64FA0D3CF672F9F3DA2051B3404SJCPEX01CL03cit_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I reached out to the GSoC people to get information on why we were n= ot accepted.  The response is not surprising:

Carol writes:
"We had to make a lot of hard decisions with our GSo= C organizations this year, and unfortunately yours was one of them. We focu= sed a lot on trying to make space and accept new, small organizations who h= ave never participated before, and we felt it wouldn't be an extreme hardship for your organization to take a year of= f from the program. I hope you all will apply again in a future year, and g= ood luck with everything this year!"

Russ Pavlicek
Xen Project Evangelist, Citrix Systems
Home Office: +1-301-829-5327
Mobile: +1-301-814-1143
UK VoIP: +44 1223 852 894
From: xen-devel-bounces@lists.xen.org [xe= n-devel-bounces@lists.xen.org] on behalf of Lars Kurth [lars.kurth.xen@gmai= l.com]
Sent: Wednesday, March 04, 2015 12:31 PM
To: xen-devel; xen-api@lists.xenproject.org; mirageos-devel; embedde= d-pv-devel@lists.xenproject.org
Cc: advisory-board@lists.xenproject.org; Russ Pavlicek
Subject: [Xen-devel] GSoC 2015 - Not accepted ... but some mentoring= organisations which have several Xen related projects in them are

Hi folks,

just a quick note to let you know that we were not accepted= for GSoC this year. Do note that the Linux Foundation, OpenStack Foundatio= n and many of the other usual suspects have not been accepted this year. We= will find out more why on Friday. However, there are at least 4 Xen related projects that are managed by oth= er
 
I made a note at the top of http://wiki.xenproject.org/wiki/Archived/GSoC_2015 to point applic= ants to some of those projects. I have found 5 so far (which may bot be a c= omplete list):
Other projects which were accepted are QEMU: note that there are no Xen related projects, but giv= en that Xen has good relationships with the QEMU community we may be able to get one or two projects onto the list if someo= ne steps up and is willing to mentor

Best Regards
Lars
--_000_55E78A57290FB64FA0D3CF672F9F3DA2051B3404SJCPEX01CL03cit_-- --===============3321188397230113095== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============3321188397230113095==-- From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 10 15:28:38 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 10 Mar 2015 15:28:38 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YVM5G-0007ZR-Dm; Tue, 10 Mar 2015 15:28:38 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YUr0C-0004LA-Gl for embedded-pv-devel@lists.xenproject.org; Mon, 09 Mar 2015 06:17:20 +0000 Received: from [193.109.254.147] by server-2.bemta-14.messagelabs.com id 80/8C-31919-FEA3DF45; Mon, 09 Mar 2015 06:17:19 +0000 X-Env-Sender: sumadhurakalyan@gmail.com X-Msg-Ref: server-3.tower-27.messagelabs.com!1425881835!15593666!1 X-Originating-IP: [209.85.223.177] X-SpamReason: No, hits=0.4 required=7.0 tests=HTML_50_60,HTML_MESSAGE, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 4262 invoked from network); 9 Mar 2015 06:17:16 -0000 Received: from mail-ie0-f177.google.com (HELO mail-ie0-f177.google.com) (209.85.223.177) by server-3.tower-27.messagelabs.com with RC4-SHA encrypted SMTP; 9 Mar 2015 06:17:16 -0000 Received: by iery20 with SMTP id y20so6988616ier.11 for ; Sun, 08 Mar 2015 23:17:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:from:date:message-id:subject:to:content-type; bh=89LkBbvxpMIgwQ/FFCBO/9jo3bKJfiKMxYDb0+V8gy0=; b=XCqMFmvM0G0P1JPhrHBtRvX09QWvkpmEyX6X4faL89g/8n2j+WtMoyWWrdjwY4HZU5 B/WPFPEUqoB/JLs7NhqJTk2+6PxUnmxUlIdT4jBKF1HhgPNm/0XP+nw248wEZ9H/oU2U k09CJ5i6vs1dECJ1ZrGoS0LJe79eDBW2MtKjC2NbKky0HdEpk8MOB/uKBTYn+rtktNnE jfQXYQ2mRo8sg7kwRV67yta2mrSyPTqBTZiETIUCKij5Jzu7DxaaoCkoxQyCHCVkYNkh 1vjhFtiBrwxB48/GUOivqNbc9oZO9lub0BsJ6/zbob0yBB9dsOiHewYhUVAkL/RFzQxf H+Fw== X-Received: by 10.107.9.88 with SMTP id j85mr33953917ioi.60.1425881835478; Sun, 08 Mar 2015 23:17:15 -0700 (PDT) MIME-Version: 1.0 Received: by 10.107.157.135 with HTTP; Sun, 8 Mar 2015 23:16:55 -0700 (PDT) From: Sumadhura Kalyan Date: Mon, 9 Mar 2015 11:46:55 +0530 Message-ID: To: embedded-pv-devel@lists.xenproject.org X-Mailman-Approved-At: Tue, 10 Mar 2015 15:28:37 +0000 Subject: [Embedded-pv-devel] Android on Xen X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============8405942414333586819==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============8405942414333586819== Content-Type: multipart/alternative; boundary=001a113f8d344ba6320510d4fc13 --001a113f8d344ba6320510d4fc13 Content-Type: text/plain; charset=UTF-8 Hi, I want to install android JB in DomU for xen4.5 Hypervisor,Idon't know what are configuration i have to change.I only did fstab file.and my hardware is exynos5250. Still it not changing any booting up.Is there any thing to configure ,can i know the processes regarding how to boot up the android on xen ARM as guest os. -- *Regards,* *s.kalyan,* *9292050807.* --001a113f8d344ba6320510d4fc13 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable



Hi,
I want to install android JB in DomU= for xen4.5 Hypervisor,Idon't know
what are configur= ation i have to change.I only did fstab file.and my
hard= ware is exynos5250. Still it not changing any booting up.Is there any thing= to configure ,can i know the processes regarding =C2=A0 how to boot up the= android on xen ARM as guest os.



--
Regards,
s.kalyan,
9292050807.
--001a113f8d344ba6320510d4fc13-- --===============8405942414333586819== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============8405942414333586819==-- From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 10 15:28:38 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 10 Mar 2015 15:28:38 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YVM5G-0007ZM-CR; Tue, 10 Mar 2015 15:28:38 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YTw7i-0000sZ-I9; Fri, 06 Mar 2015 17:33:18 +0000 Received: from [85.158.139.211] by server-1.bemta-5.messagelabs.com id 13/7B-25903-DD4E9F45; Fri, 06 Mar 2015 17:33:17 +0000 X-Env-Sender: russell.pavlicek@citrix.com X-Msg-Ref: server-3.tower-206.messagelabs.com!1425663193!6048827!1 X-Originating-IP: [66.165.176.63] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni42MyA9PiAzMDYwNDg=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 18886 invoked from network); 6 Mar 2015 17:33:16 -0000 Received: from smtp02.citrix.com (HELO SMTP02.CITRIX.COM) (66.165.176.63) by server-3.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 6 Mar 2015 17:33:16 -0000 X-IronPort-AV: E=Sophos;i="5.11,354,1422921600"; d="scan'208,217";a="242554733" From: Russell Pavlicek To: Lars Kurth , xen-devel , "xen-api@lists.xenproject.org" , mirageos-devel , "embedded-pv-devel@lists.xenproject.org" Thread-Topic: [Xen-devel] GSoC 2015 - Not accepted ... but some mentoring organisations which have several Xen related projects in them are Thread-Index: AQHQWDN0yLBVQRkuaUmt9oendKk+9A== Date: Fri, 6 Mar 2015 17:32:36 +0000 Message-ID: <55E78A57290FB64FA0D3CF672F9F3DA2051B3404@SJCPEX01CL03.citrite.net> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: MIME-Version: 1.0 X-Mailman-Approved-At: Tue, 10 Mar 2015 15:28:37 +0000 Cc: "advisory-board@lists.xenproject.org" Subject: Re: [Embedded-pv-devel] [Xen-devel] GSoC 2015 - Not accepted ... but some mentoring organisations which have several Xen related projects in them are X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============3321188397230113095==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============3321188397230113095== Content-Language: en-US Content-Type: multipart/alternative; boundary="_000_55E78A57290FB64FA0D3CF672F9F3DA2051B3404SJCPEX01CL03cit_" --_000_55E78A57290FB64FA0D3CF672F9F3DA2051B3404SJCPEX01CL03cit_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I reached out to the GSoC people to get information on why we were not acce= pted. The response is not surprising: Carol writes: "We had to make a lot of hard decisions with our GSoC organizations this ye= ar, and unfortunately yours was one of them. We focused a lot on trying to = make space and accept new, small organizations who have never participated = before, and we felt it wouldn't be an extreme hardship for your organizatio= n to take a year off from the program. I hope you all will apply again in a= future year, and good luck with everything this year!" Russ Pavlicek Xen Project Evangelist, Citrix Systems Home Office: +1-301-829-5327 Mobile: +1-301-814-1143 UK VoIP: +44 1223 852 894 ________________________________ From: xen-devel-bounces@lists.xen.org [xen-devel-bounces@lists.xen.org] on = behalf of Lars Kurth [lars.kurth.xen@gmail.com] Sent: Wednesday, March 04, 2015 12:31 PM To: xen-devel; xen-api@lists.xenproject.org; mirageos-devel; embedded-pv-de= vel@lists.xenproject.org Cc: advisory-board@lists.xenproject.org; Russ Pavlicek Subject: [Xen-devel] GSoC 2015 - Not accepted ... but some mentoring organi= sations which have several Xen related projects in them are Hi folks, just a quick note to let you know that we were not accepted for GSoC this y= ear. Do note that the Linux Foundation, OpenStack Foundation and many of th= e other usual suspects have not been accepted this year. We will find out m= ore why on Friday. However, there are at least 4 Xen related projects that = are managed by other I made a note at the top of http://wiki.xenproject.org/wiki/Archived/GSoC_2= 015 to point applicants to some of those projects. I have found 5 so far (w= hich may bot be a complete list): * Xen based Hypervisor in a Box @ Centos * Xen guest support for OpenBSD @ Open BSD Foundation * 3 Xen related projects @ Ganeti Other projects which were accepted are QEMU: note that there are no Xen related project= s, but given that Xen has good relationships with the QEMU community we may= be able to get one or two projects onto the list if someone steps up and i= s willing to mentor Best Regards Lars --_000_55E78A57290FB64FA0D3CF672F9F3DA2051B3404SJCPEX01CL03cit_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I reached out to the GSoC people to get information on why we were n= ot accepted.  The response is not surprising:

Carol writes:
"We had to make a lot of hard decisions with our GSo= C organizations this year, and unfortunately yours was one of them. We focu= sed a lot on trying to make space and accept new, small organizations who h= ave never participated before, and we felt it wouldn't be an extreme hardship for your organization to take a year of= f from the program. I hope you all will apply again in a future year, and g= ood luck with everything this year!"

Russ Pavlicek
Xen Project Evangelist, Citrix Systems
Home Office: +1-301-829-5327
Mobile: +1-301-814-1143
UK VoIP: +44 1223 852 894
From: xen-devel-bounces@lists.xen.org [xe= n-devel-bounces@lists.xen.org] on behalf of Lars Kurth [lars.kurth.xen@gmai= l.com]
Sent: Wednesday, March 04, 2015 12:31 PM
To: xen-devel; xen-api@lists.xenproject.org; mirageos-devel; embedde= d-pv-devel@lists.xenproject.org
Cc: advisory-board@lists.xenproject.org; Russ Pavlicek
Subject: [Xen-devel] GSoC 2015 - Not accepted ... but some mentoring= organisations which have several Xen related projects in them are

Hi folks,

just a quick note to let you know that we were not accepted= for GSoC this year. Do note that the Linux Foundation, OpenStack Foundatio= n and many of the other usual suspects have not been accepted this year. We= will find out more why on Friday. However, there are at least 4 Xen related projects that are managed by oth= er
 
I made a note at the top of http://wiki.xenproject.org/wiki/Archived/GSoC_2015 to point applic= ants to some of those projects. I have found 5 so far (which may bot be a c= omplete list):
Other projects which were accepted are QEMU: note that there are no Xen related projects, but giv= en that Xen has good relationships with the QEMU community we may be able to get one or two projects onto the list if someo= ne steps up and is willing to mentor

Best Regards
Lars
--_000_55E78A57290FB64FA0D3CF672F9F3DA2051B3404SJCPEX01CL03cit_-- --===============3321188397230113095== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============3321188397230113095==-- From embedded-pv-devel-bounces@lists.xenproject.org Wed Mar 11 20:39:36 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Wed, 11 Mar 2015 20:39:36 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YVnPk-0008Sv-9s; Wed, 11 Mar 2015 20:39:36 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YVnPi-0008Sq-IW for embedded-pv-devel@lists.xenproject.org; Wed, 11 Mar 2015 20:39:34 +0000 Received: from [193.109.254.147] by server-3.bemta-14.messagelabs.com id 39/2D-10964-508A0055; Wed, 11 Mar 2015 20:39:33 +0000 X-Env-Sender: andrii.tseglytskyi@globallogic.com X-Msg-Ref: server-5.tower-27.messagelabs.com!1426106370!7456054!1 X-Originating-IP: [64.18.0.251] X-SpamReason: No, hits=0.6 required=7.0 tests=HTML_60_70,HTML_MESSAGE, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 10020 invoked from network); 11 Mar 2015 20:39:32 -0000 Received: from exprod5og126.obsmtp.com (HELO exprod5og126.obsmtp.com) (64.18.0.251) by server-5.tower-27.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 11 Mar 2015 20:39:32 -0000 Received: from mail-qc0-f179.google.com ([209.85.216.179]) (using TLSv1) by exprod5ob126.postini.com ([64.18.4.12]) with SMTP ID DSNKVQCoAp4ewMjA48XkaxdXDHIz04AllJ9c@postini.com; Wed, 11 Mar 2015 13:39:32 PDT Received: by qcvx3 with SMTP id x3so13560665qcv.0 for ; Wed, 11 Mar 2015 13:39:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=xjd4QrrLdNwFO+0TMLvZSnS1RXPLPE2E1+Oja9NJdk4=; b=JwCFscjQXjmMbv+53NhfJw4TBIn8xG5CQ2lCpQYvJxeKD2NTZF1OYGofBJJqwYyEZK 5C61//2D5Cw5OJUyHSIfy8yELjUET8b0twP1mRdgljCB/eEl2Jwz0kgtcpJSbN59UTdD p9Uw2nTKGTbbtodn/smZ7qCK5oI39z30LQSO8= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=xjd4QrrLdNwFO+0TMLvZSnS1RXPLPE2E1+Oja9NJdk4=; b=nNReh3Q/I2x+hT/O859l5BLy3R7rJgmpIsmlBisz3ZpSSqAL1zFRdZm+3J4rtPEe28 mxg9+bPnGxLaKbsFzm4SfFTuZZayIqGotmJETIbcK0MPeXo9dIu9/KQeDVVP+gRNrqCH LDO76E/b5g76zeDdcH18HF2zY9lihGOTGtwZDlKUe6RjtFI0GU3lPMrvT3sizHCAzzTz k82f2b7rGabubyV11gBWXMZiq1+MXYKCj7PwBpmUMFmnNwc6jhFHXVVDslnjNYGBvYmW KwjfpEf19QY8zrRVx4IdIpXwR2T7kcS4oDQVGILPZfsJB6FGHqq/bbCLdgHTWVtb58/b nEHA== X-Gm-Message-State: ALoCoQnAYLtgKcFa8FAgRKYm2YqoG3iFJsrq8HztL+EDOz47rcJvpZoqkQMpdOSJZUnL+9eYi9Fu/d+jxT9iqngmXwKVws+TzsmdVS5fYSq+3yOovIW34xfVrduGHtrVg6wLQczGceSLFGemi45FNw9HVVUIurnVFBKdOEkEDWEmoZHIIVOIVdk= X-Received: by 10.140.234.17 with SMTP id f17mr52455379qhc.64.1426106369631; Wed, 11 Mar 2015 13:39:29 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.140.234.17 with SMTP id f17mr52455367qhc.64.1426106369494; Wed, 11 Mar 2015 13:39:29 -0700 (PDT) Received: by 10.140.254.8 with HTTP; Wed, 11 Mar 2015 13:39:29 -0700 (PDT) In-Reply-To: References: Date: Wed, 11 Mar 2015 22:39:29 +0200 Message-ID: From: Andrii Tseglytskyi To: Sumadhura Kalyan Cc: embedded-pv-devel@lists.xenproject.org Subject: Re: [Embedded-pv-devel] Android on Xen X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============7580469483045506728==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============7580469483045506728== Content-Type: multipart/alternative; boundary=001a11354b9491069a0511094317 --001a11354b9491069a0511094317 Content-Type: text/plain; charset=UTF-8 Hi Sumadhura, Running Android as domU is not a trivial. I would suggest to proceed in the following steps: 1. Run Android kernel. In general Android kernel is Linux kernel. The only you may need here is to disable as lot hardware as possible. 2. Run Graphic and Video. You need to passthrough GPU / IPU hardware to domU. 3. Run sound / network / display etc. You need PV drivers for that. Some of them are already in baseline (network), some exist as RFC patches. Can you please specify in details - have you succeed to run an Android kernel? Regards, Andrii On Mon, Mar 9, 2015 at 8:16 AM, Sumadhura Kalyan wrote: > > > > Hi, > I want to install android JB in DomU for xen4.5 Hypervisor,Idon't know > what are configuration i have to change.I only did fstab file.and my > hardware is exynos5250. Still it not changing any booting up.Is there any > thing to configure ,can i know the processes regarding how to boot up the > android on xen ARM as guest os. > > > > -- > *Regards,* > *s.kalyan,* > *9292050807.* > > _______________________________________________ > Embedded-pv-devel mailing list > Embedded-pv-devel@lists.xenproject.org > http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel > -- Andrii Tseglytskyi | Lead engineer GlobalLogic www.globallogic.com --001a11354b9491069a0511094317 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Hi=C2=A0Sumadhura,

Running Android as d= omU is not a trivial. I would suggest to proceed in the following steps:

1. Run Android kernel.
In general Android = kernel is Linux kernel. The only you may need here is to disable as lot har= dware as possible.

2. Run Graphic and Video.
=
You need to passthrough GPU / IPU hardware to domU.

3. Run sound / network / display etc.
You need PV drivers = for that. Some of them are already in baseline (network), some exist as RFC= patches.

Can you please specify in details - have= you succeed to run an Android kernel?

Regards,
Andrii



On Mon, Mar 9, 2015 at 8:16 AM, Suma= dhura Kalyan <sumadhurakalyan@gmail.com> wrote:
<= blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px= #ccc solid;padding-left:1ex">
<= br>

Hi,
I want= to install android JB in DomU for xen4.5 Hypervisor,Idon't know=
what are configuration i have to change.I only did fstab file.= and my
hardware is exynos5250. Still it not changing any= booting up.Is there any thing to configure ,can i know the processes regar= ding =C2=A0 how to boot up the android on xen ARM as guest os.
=



--
Regards,
s.kalyan,
9292050807.

_______________________________________________
Embedded-pv-devel mailing list
Embedded-pv-devel= @lists.xenproject.org
http://lists.xenproject.org/cgi-bin/mailman/listi= nfo/embedded-pv-devel


=
--

Andrii Tseglytskyi | Lead engi= neer
GlobalLogic
<= a href=3D"http://www.globallogic.com/" target=3D"_blank">www.globallogic.com
--001a11354b9491069a0511094317-- --===============7580469483045506728== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============7580469483045506728==-- From embedded-pv-devel-bounces@lists.xenproject.org Wed Mar 11 20:39:36 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Wed, 11 Mar 2015 20:39:36 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YVnPk-0008Sv-9s; Wed, 11 Mar 2015 20:39:36 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YVnPi-0008Sq-IW for embedded-pv-devel@lists.xenproject.org; Wed, 11 Mar 2015 20:39:34 +0000 Received: from [193.109.254.147] by server-3.bemta-14.messagelabs.com id 39/2D-10964-508A0055; Wed, 11 Mar 2015 20:39:33 +0000 X-Env-Sender: andrii.tseglytskyi@globallogic.com X-Msg-Ref: server-5.tower-27.messagelabs.com!1426106370!7456054!1 X-Originating-IP: [64.18.0.251] X-SpamReason: No, hits=0.6 required=7.0 tests=HTML_60_70,HTML_MESSAGE, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 10020 invoked from network); 11 Mar 2015 20:39:32 -0000 Received: from exprod5og126.obsmtp.com (HELO exprod5og126.obsmtp.com) (64.18.0.251) by server-5.tower-27.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 11 Mar 2015 20:39:32 -0000 Received: from mail-qc0-f179.google.com ([209.85.216.179]) (using TLSv1) by exprod5ob126.postini.com ([64.18.4.12]) with SMTP ID DSNKVQCoAp4ewMjA48XkaxdXDHIz04AllJ9c@postini.com; Wed, 11 Mar 2015 13:39:32 PDT Received: by qcvx3 with SMTP id x3so13560665qcv.0 for ; Wed, 11 Mar 2015 13:39:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=xjd4QrrLdNwFO+0TMLvZSnS1RXPLPE2E1+Oja9NJdk4=; b=JwCFscjQXjmMbv+53NhfJw4TBIn8xG5CQ2lCpQYvJxeKD2NTZF1OYGofBJJqwYyEZK 5C61//2D5Cw5OJUyHSIfy8yELjUET8b0twP1mRdgljCB/eEl2Jwz0kgtcpJSbN59UTdD p9Uw2nTKGTbbtodn/smZ7qCK5oI39z30LQSO8= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=xjd4QrrLdNwFO+0TMLvZSnS1RXPLPE2E1+Oja9NJdk4=; b=nNReh3Q/I2x+hT/O859l5BLy3R7rJgmpIsmlBisz3ZpSSqAL1zFRdZm+3J4rtPEe28 mxg9+bPnGxLaKbsFzm4SfFTuZZayIqGotmJETIbcK0MPeXo9dIu9/KQeDVVP+gRNrqCH LDO76E/b5g76zeDdcH18HF2zY9lihGOTGtwZDlKUe6RjtFI0GU3lPMrvT3sizHCAzzTz k82f2b7rGabubyV11gBWXMZiq1+MXYKCj7PwBpmUMFmnNwc6jhFHXVVDslnjNYGBvYmW KwjfpEf19QY8zrRVx4IdIpXwR2T7kcS4oDQVGILPZfsJB6FGHqq/bbCLdgHTWVtb58/b nEHA== X-Gm-Message-State: ALoCoQnAYLtgKcFa8FAgRKYm2YqoG3iFJsrq8HztL+EDOz47rcJvpZoqkQMpdOSJZUnL+9eYi9Fu/d+jxT9iqngmXwKVws+TzsmdVS5fYSq+3yOovIW34xfVrduGHtrVg6wLQczGceSLFGemi45FNw9HVVUIurnVFBKdOEkEDWEmoZHIIVOIVdk= X-Received: by 10.140.234.17 with SMTP id f17mr52455379qhc.64.1426106369631; Wed, 11 Mar 2015 13:39:29 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.140.234.17 with SMTP id f17mr52455367qhc.64.1426106369494; Wed, 11 Mar 2015 13:39:29 -0700 (PDT) Received: by 10.140.254.8 with HTTP; Wed, 11 Mar 2015 13:39:29 -0700 (PDT) In-Reply-To: References: Date: Wed, 11 Mar 2015 22:39:29 +0200 Message-ID: From: Andrii Tseglytskyi To: Sumadhura Kalyan Cc: embedded-pv-devel@lists.xenproject.org Subject: Re: [Embedded-pv-devel] Android on Xen X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============7580469483045506728==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============7580469483045506728== Content-Type: multipart/alternative; boundary=001a11354b9491069a0511094317 --001a11354b9491069a0511094317 Content-Type: text/plain; charset=UTF-8 Hi Sumadhura, Running Android as domU is not a trivial. I would suggest to proceed in the following steps: 1. Run Android kernel. In general Android kernel is Linux kernel. The only you may need here is to disable as lot hardware as possible. 2. Run Graphic and Video. You need to passthrough GPU / IPU hardware to domU. 3. Run sound / network / display etc. You need PV drivers for that. Some of them are already in baseline (network), some exist as RFC patches. Can you please specify in details - have you succeed to run an Android kernel? Regards, Andrii On Mon, Mar 9, 2015 at 8:16 AM, Sumadhura Kalyan wrote: > > > > Hi, > I want to install android JB in DomU for xen4.5 Hypervisor,Idon't know > what are configuration i have to change.I only did fstab file.and my > hardware is exynos5250. Still it not changing any booting up.Is there any > thing to configure ,can i know the processes regarding how to boot up the > android on xen ARM as guest os. > > > > -- > *Regards,* > *s.kalyan,* > *9292050807.* > > _______________________________________________ > Embedded-pv-devel mailing list > Embedded-pv-devel@lists.xenproject.org > http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel > -- Andrii Tseglytskyi | Lead engineer GlobalLogic www.globallogic.com --001a11354b9491069a0511094317 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Hi=C2=A0Sumadhura,

Running Android as d= omU is not a trivial. I would suggest to proceed in the following steps:

1. Run Android kernel.
In general Android = kernel is Linux kernel. The only you may need here is to disable as lot har= dware as possible.

2. Run Graphic and Video.
=
You need to passthrough GPU / IPU hardware to domU.

3. Run sound / network / display etc.
You need PV drivers = for that. Some of them are already in baseline (network), some exist as RFC= patches.

Can you please specify in details - have= you succeed to run an Android kernel?

Regards,
Andrii



On Mon, Mar 9, 2015 at 8:16 AM, Suma= dhura Kalyan <sumadhurakalyan@gmail.com> wrote:
<= blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px= #ccc solid;padding-left:1ex">
<= br>

Hi,
I want= to install android JB in DomU for xen4.5 Hypervisor,Idon't know=
what are configuration i have to change.I only did fstab file.= and my
hardware is exynos5250. Still it not changing any= booting up.Is there any thing to configure ,can i know the processes regar= ding =C2=A0 how to boot up the android on xen ARM as guest os.
=



--
Regards,
s.kalyan,
9292050807.

_______________________________________________
Embedded-pv-devel mailing list
Embedded-pv-devel= @lists.xenproject.org
http://lists.xenproject.org/cgi-bin/mailman/listi= nfo/embedded-pv-devel


=
--

Andrii Tseglytskyi | Lead engi= neer
GlobalLogic
<= a href=3D"http://www.globallogic.com/" target=3D"_blank">www.globallogic.com
--001a11354b9491069a0511094317-- --===============7580469483045506728== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============7580469483045506728==-- From embedded-pv-devel-bounces@lists.xenproject.org Thu Mar 12 18:14:40 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Thu, 12 Mar 2015 18:14:40 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YW7d1-0005hF-Mv; Thu, 12 Mar 2015 18:14:39 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YW7cz-0005gj-W0 for embedded-pv-devel@lists.xenproject.org; Thu, 12 Mar 2015 18:14:38 +0000 Received: from [85.158.139.211] by server-6.bemta-5.messagelabs.com id FB/52-30108-D87D1055; Thu, 12 Mar 2015 18:14:37 +0000 X-Env-Sender: lars.kurth.xen@gmail.com X-Msg-Ref: server-15.tower-206.messagelabs.com!1426184076!8043323!1 X-Originating-IP: [209.85.212.181] X-SpamReason: No, hits=1.1 required=7.0 tests=BODY_RANDOM_LONG,DIET_1 X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 23227 invoked from network); 12 Mar 2015 18:14:36 -0000 Received: from mail-wi0-f181.google.com (HELO mail-wi0-f181.google.com) (209.85.212.181) by server-15.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 12 Mar 2015 18:14:36 -0000 Received: by widfb4 with SMTP id fb4so6206827wid.0 for ; Thu, 12 Mar 2015 11:14:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=Z3B9IBYwG4e/JeScl9lMahGDtD06EmJI9+0p86BTrUY=; b=TZ6unplHK8pplvvvGRxYcaEjj/wFn0gXZ3STbRKARSgGsDTrkGjvJSY1ZSByUmidoT tIXbEGqLRZwSsKIMfVoUnVGgfidqqDcMEhY+7niq1tkFilfLkKmKSuf+z1pYCF6GIZOz L9h2kdDDbQJUeI7aSE/dF0y8oQCehk+cciPjNHafK7JeMhQZ7c8GqNJu+bRrFd+GyxOD DWXzFwsPZ0HrTKgAIMGOHoYKwhDzKXYDg3ihgl11pQKXxHwPjambAooIBW7Ks+bVRsea NCa5k+//4pMib8q3C5AkR0kOyth9QYf3iDMeoGISxidiXSTP4wC7GnUSzWcc+C+59xl7 LNVA== X-Received: by 10.194.63.16 with SMTP id c16mr91151945wjs.117.1426184076217; Thu, 12 Mar 2015 11:14:36 -0700 (PDT) Received: from dhcp-3-49.uk.xensource.com ([185.25.64.249]) by mx.google.com with ESMTPSA id gd6sm12199094wib.17.2015.03.12.11.14.32 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 12 Mar 2015 11:14:34 -0700 (PDT) Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) From: Lars Kurth In-Reply-To: <1424713267.27930.250.camel@citrix.com> Date: Thu, 12 Mar 2015 18:14:33 +0000 Message-Id: <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> References: <1423222117-18949-1-git-send-email-oleksandr.dmytryshyn@globallogic.com> <1424713267.27930.250.camel@citrix.com> To: Ian Campbell X-Mailer: Apple Mail (2.2070.6) Cc: Iurii Konovalenko , Keir Fraser , Tim Deegan , Oleksandr Dmytryshyn , Ian Jackson , xen-devel@lists.xen.org, embedded-pv-devel@lists.xenproject.org, Lars Kurth , Stefano Panella , Jan Beulich , Andrew Cooper , DarioFaggioli , PaulDurrant , =?utf-8?Q?RogerPauMonn=C3=A9?= Subject: Re: [Embedded-pv-devel] [PATCH v7] sndif: add ABI for Para-virtual sound X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org > On 23 Feb 2015, at 17:41, Ian Campbell wrote: > > On Fri, 2015-02-06 at 13:28 +0200, Oleksandr Dmytryshyn wrote: >> This is ABI for the two halves of a Para-virtual >> sound driver to communicate with each to other. >> >> Signed-off-by: Oleksandr Dmytryshyn >> Signed-off-by: Iurii Konovalenko > > This seems to have gotten rather stalled, I think because of two > factors, one is that noone has clear maintainer responsibility for > blessing the creation of new PV protocols and partly because people are > naturally a bit cautious about creating new ABIs, which must be > maintained long term, for types of device with which they are not really > familiar. > > I've added Lars because perhaps there is some process we can put in > place which helps alleviate these issues. (I don't know what, but > perhaps a "staging area" for new protocols which isn't ABI stable along > with some sort of graduation process, or perhaps some sort of governance > thing which would make it clear who has to say yes to something like > this, so we can beat them with sticks until they say something). Hi,I nearly missed this. Please make sure you forward stuff and change the headline if you want me to look into things. Otherwise I may miss it. >From my perspective, this exactly the kind of scenario why we created the embedded / automotive subproject, with an option to store code in repos owned by the project. Given that the primary use-case of these drivers is embedded / automotive, my suggestion would be to 1.a) Use a repo in the embedded / automotive pv driver subproject to host the spec - but use a file system structure that matches the xen tree 1.b) I would assume there would be one back-end and several front-ends for these drivers and some would eventually appear in trees owned by the embedded / automotive pv driver subproject In this case, the maintainer responsibility would fall to members of the embedded / automotive pv driver subproject. Once there are several implementations, and enough people with skills to review we can re-visit where the spec and drivers live. We can have a discussion about criteria of when to move, but I don't think that makes a lot of sense. I think the concerns that need to be addressed are: 2.a) Enough skills to review the code / protocols from different stake-holders - this should happen with time, once the spec and code are there. And of course once the embedded / automotive pv driver subproject graduates, that will also give extra weight to its maintainers in the wider community 2.b) Of course if there was a strong case that PV sound drivers are extremely useful for core data centre use-cases, I would probably suggest another approach Maybe 2.b) needs to be checked with Intel folks - there may be some sound requirement for XenGT Would this work as a way forward? Regards Lars _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Thu Mar 12 18:14:40 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Thu, 12 Mar 2015 18:14:40 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YW7d1-0005hF-Mv; Thu, 12 Mar 2015 18:14:39 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YW7cz-0005gj-W0 for embedded-pv-devel@lists.xenproject.org; Thu, 12 Mar 2015 18:14:38 +0000 Received: from [85.158.139.211] by server-6.bemta-5.messagelabs.com id FB/52-30108-D87D1055; Thu, 12 Mar 2015 18:14:37 +0000 X-Env-Sender: lars.kurth.xen@gmail.com X-Msg-Ref: server-15.tower-206.messagelabs.com!1426184076!8043323!1 X-Originating-IP: [209.85.212.181] X-SpamReason: No, hits=1.1 required=7.0 tests=BODY_RANDOM_LONG,DIET_1 X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 23227 invoked from network); 12 Mar 2015 18:14:36 -0000 Received: from mail-wi0-f181.google.com (HELO mail-wi0-f181.google.com) (209.85.212.181) by server-15.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 12 Mar 2015 18:14:36 -0000 Received: by widfb4 with SMTP id fb4so6206827wid.0 for ; Thu, 12 Mar 2015 11:14:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=Z3B9IBYwG4e/JeScl9lMahGDtD06EmJI9+0p86BTrUY=; b=TZ6unplHK8pplvvvGRxYcaEjj/wFn0gXZ3STbRKARSgGsDTrkGjvJSY1ZSByUmidoT tIXbEGqLRZwSsKIMfVoUnVGgfidqqDcMEhY+7niq1tkFilfLkKmKSuf+z1pYCF6GIZOz L9h2kdDDbQJUeI7aSE/dF0y8oQCehk+cciPjNHafK7JeMhQZ7c8GqNJu+bRrFd+GyxOD DWXzFwsPZ0HrTKgAIMGOHoYKwhDzKXYDg3ihgl11pQKXxHwPjambAooIBW7Ks+bVRsea NCa5k+//4pMib8q3C5AkR0kOyth9QYf3iDMeoGISxidiXSTP4wC7GnUSzWcc+C+59xl7 LNVA== X-Received: by 10.194.63.16 with SMTP id c16mr91151945wjs.117.1426184076217; Thu, 12 Mar 2015 11:14:36 -0700 (PDT) Received: from dhcp-3-49.uk.xensource.com ([185.25.64.249]) by mx.google.com with ESMTPSA id gd6sm12199094wib.17.2015.03.12.11.14.32 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 12 Mar 2015 11:14:34 -0700 (PDT) Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) From: Lars Kurth In-Reply-To: <1424713267.27930.250.camel@citrix.com> Date: Thu, 12 Mar 2015 18:14:33 +0000 Message-Id: <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> References: <1423222117-18949-1-git-send-email-oleksandr.dmytryshyn@globallogic.com> <1424713267.27930.250.camel@citrix.com> To: Ian Campbell X-Mailer: Apple Mail (2.2070.6) Cc: Iurii Konovalenko , Keir Fraser , Tim Deegan , Oleksandr Dmytryshyn , Ian Jackson , xen-devel@lists.xen.org, embedded-pv-devel@lists.xenproject.org, Lars Kurth , Stefano Panella , Jan Beulich , Andrew Cooper , DarioFaggioli , PaulDurrant , =?utf-8?Q?RogerPauMonn=C3=A9?= Subject: Re: [Embedded-pv-devel] [PATCH v7] sndif: add ABI for Para-virtual sound X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org > On 23 Feb 2015, at 17:41, Ian Campbell wrote: > > On Fri, 2015-02-06 at 13:28 +0200, Oleksandr Dmytryshyn wrote: >> This is ABI for the two halves of a Para-virtual >> sound driver to communicate with each to other. >> >> Signed-off-by: Oleksandr Dmytryshyn >> Signed-off-by: Iurii Konovalenko > > This seems to have gotten rather stalled, I think because of two > factors, one is that noone has clear maintainer responsibility for > blessing the creation of new PV protocols and partly because people are > naturally a bit cautious about creating new ABIs, which must be > maintained long term, for types of device with which they are not really > familiar. > > I've added Lars because perhaps there is some process we can put in > place which helps alleviate these issues. (I don't know what, but > perhaps a "staging area" for new protocols which isn't ABI stable along > with some sort of graduation process, or perhaps some sort of governance > thing which would make it clear who has to say yes to something like > this, so we can beat them with sticks until they say something). Hi,I nearly missed this. Please make sure you forward stuff and change the headline if you want me to look into things. Otherwise I may miss it. >From my perspective, this exactly the kind of scenario why we created the embedded / automotive subproject, with an option to store code in repos owned by the project. Given that the primary use-case of these drivers is embedded / automotive, my suggestion would be to 1.a) Use a repo in the embedded / automotive pv driver subproject to host the spec - but use a file system structure that matches the xen tree 1.b) I would assume there would be one back-end and several front-ends for these drivers and some would eventually appear in trees owned by the embedded / automotive pv driver subproject In this case, the maintainer responsibility would fall to members of the embedded / automotive pv driver subproject. Once there are several implementations, and enough people with skills to review we can re-visit where the spec and drivers live. We can have a discussion about criteria of when to move, but I don't think that makes a lot of sense. I think the concerns that need to be addressed are: 2.a) Enough skills to review the code / protocols from different stake-holders - this should happen with time, once the spec and code are there. And of course once the embedded / automotive pv driver subproject graduates, that will also give extra weight to its maintainers in the wider community 2.b) Of course if there was a strong case that PV sound drivers are extremely useful for core data centre use-cases, I would probably suggest another approach Maybe 2.b) needs to be checked with Intel folks - there may be some sound requirement for XenGT Would this work as a way forward? Regards Lars _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 13 12:43:29 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 13 Mar 2015 12:43:29 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YWOw5-0003A1-K5; Fri, 13 Mar 2015 12:43:29 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YWOw4-00039i-B4; Fri, 13 Mar 2015 12:43:28 +0000 Received: from [85.158.137.68] by server-8.bemta-3.messagelabs.com id 0B/61-07208-F6BD2055; Fri, 13 Mar 2015 12:43:27 +0000 X-Env-Sender: lars.kurth.xen@gmail.com X-Msg-Ref: server-15.tower-31.messagelabs.com!1426250606!11652809!1 X-Originating-IP: [74.125.82.41] X-SpamReason: No, hits=0.0 required=7.0 tests=HTML_MESSAGE X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 562 invoked from network); 13 Mar 2015 12:43:26 -0000 Received: from mail-wg0-f41.google.com (HELO mail-wg0-f41.google.com) (74.125.82.41) by server-15.tower-31.messagelabs.com with RC4-SHA encrypted SMTP; 13 Mar 2015 12:43:26 -0000 Received: by wggx13 with SMTP id x13so22999008wgg.4; Fri, 13 Mar 2015 05:43:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:content-type:subject:message-id:date:to:mime-version; bh=/jbYMlT0Wx5FR6Enjht5drUz/qoxJEgteoNH5YCdEyU=; b=sHMYbwkEH1WJSF9VOMevP8AYgSermN2TcvfGA1qmZC403TmdUN450Y8JB3NTMgqlBw ZcZGP93ayGgL7fk9jxXKSHSfn/0PWY2DZ9/pzDtwMkjdj8FowYRzsGEM8kaSfrs2gm6Z 7SpDmqQN0l5QbatjnTMKJ4RzFPzi0nQw9sOPQWrE7AhucYN6IwCRRpF1BlZ1X5HEZk9o E5fcaHzRcEHYrAqHQjZKIxKxtaJujR0C2ASlSYO6Tag30kS+XqSkp9ZkzSEyrXBiCSyG CGM5Js8kSrBDWk7tyetft50FRWwk5Z6Ck7Duw45YUKTlX5w2eS0dle2vd6I2q+kKFRFS g9zg== X-Received: by 10.194.220.7 with SMTP id ps7mr98915600wjc.84.1426250605772; Fri, 13 Mar 2015 05:43:25 -0700 (PDT) Received: from [192.168.0.8] (97e5522d.skybroadband.com. [151.229.82.45]) by mx.google.com with ESMTPSA id 17sm2640423wjt.45.2015.03.13.05.43.23 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 13 Mar 2015 05:43:23 -0700 (PDT) From: Lars Kurth Message-Id: <9F1D4125-2B00-4E8D-B908-FF9A155F3FC2@gmail.com> Date: Fri, 13 Mar 2015 12:43:19 +0000 To: xen-devel , xen-api@lists.xenproject.org, Win-pv-devel@lists.xenproject.org, embedded-pv-devel@lists.xenproject.org, mirageos-devel@xenproject.org Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) X-Mailer: Apple Mail (2.2070.6) Subject: [Embedded-pv-devel] February AB meeting minutes published X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1538399747431118193==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============1538399747431118193== Content-Type: multipart/alternative; boundary="Apple-Mail=_21B8E93E-0CAA-4E83-94C5-F08A74F4ADBD" --Apple-Mail=_21B8E93E-0CAA-4E83-94C5-F08A74F4ADBD Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii See http://wiki.xenproject.org/wiki/AB_Meeting/February_2015_Minutes = = --Apple-Mail=_21B8E93E-0CAA-4E83-94C5-F08A74F4ADBD Content-Transfer-Encoding: 7bit Content-Type: text/html; charset=us-ascii See http://wiki.xenproject.org/wiki/AB_Meeting/February_2015_Minutes --Apple-Mail=_21B8E93E-0CAA-4E83-94C5-F08A74F4ADBD-- --===============1538399747431118193== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============1538399747431118193==-- From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 13 12:43:29 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 13 Mar 2015 12:43:29 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YWOw5-0003A1-K5; Fri, 13 Mar 2015 12:43:29 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YWOw4-00039i-B4; Fri, 13 Mar 2015 12:43:28 +0000 Received: from [85.158.137.68] by server-8.bemta-3.messagelabs.com id 0B/61-07208-F6BD2055; Fri, 13 Mar 2015 12:43:27 +0000 X-Env-Sender: lars.kurth.xen@gmail.com X-Msg-Ref: server-15.tower-31.messagelabs.com!1426250606!11652809!1 X-Originating-IP: [74.125.82.41] X-SpamReason: No, hits=0.0 required=7.0 tests=HTML_MESSAGE X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 562 invoked from network); 13 Mar 2015 12:43:26 -0000 Received: from mail-wg0-f41.google.com (HELO mail-wg0-f41.google.com) (74.125.82.41) by server-15.tower-31.messagelabs.com with RC4-SHA encrypted SMTP; 13 Mar 2015 12:43:26 -0000 Received: by wggx13 with SMTP id x13so22999008wgg.4; Fri, 13 Mar 2015 05:43:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:content-type:subject:message-id:date:to:mime-version; bh=/jbYMlT0Wx5FR6Enjht5drUz/qoxJEgteoNH5YCdEyU=; b=sHMYbwkEH1WJSF9VOMevP8AYgSermN2TcvfGA1qmZC403TmdUN450Y8JB3NTMgqlBw ZcZGP93ayGgL7fk9jxXKSHSfn/0PWY2DZ9/pzDtwMkjdj8FowYRzsGEM8kaSfrs2gm6Z 7SpDmqQN0l5QbatjnTMKJ4RzFPzi0nQw9sOPQWrE7AhucYN6IwCRRpF1BlZ1X5HEZk9o E5fcaHzRcEHYrAqHQjZKIxKxtaJujR0C2ASlSYO6Tag30kS+XqSkp9ZkzSEyrXBiCSyG CGM5Js8kSrBDWk7tyetft50FRWwk5Z6Ck7Duw45YUKTlX5w2eS0dle2vd6I2q+kKFRFS g9zg== X-Received: by 10.194.220.7 with SMTP id ps7mr98915600wjc.84.1426250605772; Fri, 13 Mar 2015 05:43:25 -0700 (PDT) Received: from [192.168.0.8] (97e5522d.skybroadband.com. [151.229.82.45]) by mx.google.com with ESMTPSA id 17sm2640423wjt.45.2015.03.13.05.43.23 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 13 Mar 2015 05:43:23 -0700 (PDT) From: Lars Kurth Message-Id: <9F1D4125-2B00-4E8D-B908-FF9A155F3FC2@gmail.com> Date: Fri, 13 Mar 2015 12:43:19 +0000 To: xen-devel , xen-api@lists.xenproject.org, Win-pv-devel@lists.xenproject.org, embedded-pv-devel@lists.xenproject.org, mirageos-devel@xenproject.org Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) X-Mailer: Apple Mail (2.2070.6) Subject: [Embedded-pv-devel] February AB meeting minutes published X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1538399747431118193==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============1538399747431118193== Content-Type: multipart/alternative; boundary="Apple-Mail=_21B8E93E-0CAA-4E83-94C5-F08A74F4ADBD" --Apple-Mail=_21B8E93E-0CAA-4E83-94C5-F08A74F4ADBD Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii See http://wiki.xenproject.org/wiki/AB_Meeting/February_2015_Minutes = = --Apple-Mail=_21B8E93E-0CAA-4E83-94C5-F08A74F4ADBD Content-Transfer-Encoding: 7bit Content-Type: text/html; charset=us-ascii See http://wiki.xenproject.org/wiki/AB_Meeting/February_2015_Minutes --Apple-Mail=_21B8E93E-0CAA-4E83-94C5-F08A74F4ADBD-- --===============1538399747431118193== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============1538399747431118193==-- From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 17 11:40:53 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 17 Mar 2015 11:40:53 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXprh-0003i4-CZ; Tue, 17 Mar 2015 11:40:53 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXprf-0003hG-Jl for embedded-pv-devel@lists.xenproject.org; Tue, 17 Mar 2015 11:40:51 +0000 Received: from [193.109.254.147] by server-13.bemta-14.messagelabs.com id B5/CF-13815-2C218055; Tue, 17 Mar 2015 11:40:50 +0000 X-Env-Sender: Ian.Campbell@citrix.com X-Msg-Ref: server-13.tower-27.messagelabs.com!1426592448!13593765!1 X-Originating-IP: [66.165.176.89] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni44OSA9PiAyMDMwMDc=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 13264 invoked from network); 17 Mar 2015 11:40:50 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-13.tower-27.messagelabs.com with RC4-SHA encrypted SMTP; 17 Mar 2015 11:40:50 -0000 X-IronPort-AV: E=Sophos;i="5.11,416,1422921600"; d="scan'208";a="244105421" Message-ID: <1426592445.18247.198.camel@citrix.com> From: Ian Campbell To: Lars Kurth Date: Tue, 17 Mar 2015 11:40:45 +0000 In-Reply-To: <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> References: <1423222117-18949-1-git-send-email-oleksandr.dmytryshyn@globallogic.com> <1424713267.27930.250.camel@citrix.com> <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> X-Mailer: Evolution 3.12.9-1+b1 MIME-Version: 1.0 X-DLP: MIA1 Cc: Iurii Konovalenko , Keir Fraser , Tim Deegan , Oleksandr Dmytryshyn , Ian Jackson , xen-devel@lists.xen.org, embedded-pv-devel@lists.xenproject.org, Lars Kurth , Stefano Panella , Jan Beulich , Andrew Cooper , DarioFaggioli , PaulDurrant , =?ISO-8859-1?Q?RogerPauMonn=E9?= Subject: Re: [Embedded-pv-devel] [PATCH v7] sndif: add ABI for Para-virtual sound X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org On Thu, 2015-03-12 at 18:14 +0000, Lars Kurth wrote: > Hi,I nearly missed this. Please make sure you forward stuff and change > the headline if you want me to look into things. Otherwise I may miss > it. Sure, I'll try and remember. FYI before Ian J went away he mentioned that he had raised some questions/issues (either on this or a previous version) which had not yet been answered (or maybe not answered to his satisfaction, I'm not sure) but that if those were addressed he would take a look with a view to acking the interface for inclusion in xen.git. (I've not looked in the threads for it, so I don't know the exact state). > From my perspective, this exactly the kind of scenario why we created > the embedded / automotive subproject, with an option to store code in > repos owned by the project. > > Given that the primary use-case of these drivers is embedded / > automotive, my suggestion would be to > 1.a) Use a repo in the embedded / automotive pv driver subproject to > host the spec - but use a file system structure that matches the xen > tree > 1.b) I would assume there would be one back-end and several front-ends > for these drivers and some would eventually appear in trees owned by > the embedded / automotive pv driver subproject > > In this case, the maintainer responsibility would fall to members of > the embedded / automotive pv driver subproject. Once there are several > implementations, and enough people with skills to review we can > re-visit where the spec and drivers live. > > We can have a discussion about criteria of when to move, but I don't > think that makes a lot of sense. I think the concerns that need to be > addressed are: > 2.a) Enough skills to review the code / protocols from different > stake-holders - this should happen with time, once the spec and code > are there. And of course once the embedded / automotive pv driver > subproject graduates, that will also give extra weight to its > maintainers in the wider community > 2.b) Of course if there was a strong case that PV sound drivers are > extremely useful for core data centre use-cases, I would probably > suggest another approach > > Maybe 2.b) needs to be checked with Intel folks - there may be some > sound requirement for XenGT > > Would this work as a way forward? I think the main things which is missing is some decision as to the the point at which we would consider the ABI for a PV protocol fixed, i.e. to be maintained in a backwards compatible manner from then on. That's of particular importance when one end of the pair is implemented in external projects (e.g. OS driver frontends). If the interface is not declared stable then changes would be allowed which would invalidate those drivers. Ian. _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 17 11:40:53 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 17 Mar 2015 11:40:53 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXprh-0003i4-CZ; Tue, 17 Mar 2015 11:40:53 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXprf-0003hG-Jl for embedded-pv-devel@lists.xenproject.org; Tue, 17 Mar 2015 11:40:51 +0000 Received: from [193.109.254.147] by server-13.bemta-14.messagelabs.com id B5/CF-13815-2C218055; Tue, 17 Mar 2015 11:40:50 +0000 X-Env-Sender: Ian.Campbell@citrix.com X-Msg-Ref: server-13.tower-27.messagelabs.com!1426592448!13593765!1 X-Originating-IP: [66.165.176.89] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni44OSA9PiAyMDMwMDc=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 13264 invoked from network); 17 Mar 2015 11:40:50 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-13.tower-27.messagelabs.com with RC4-SHA encrypted SMTP; 17 Mar 2015 11:40:50 -0000 X-IronPort-AV: E=Sophos;i="5.11,416,1422921600"; d="scan'208";a="244105421" Message-ID: <1426592445.18247.198.camel@citrix.com> From: Ian Campbell To: Lars Kurth Date: Tue, 17 Mar 2015 11:40:45 +0000 In-Reply-To: <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> References: <1423222117-18949-1-git-send-email-oleksandr.dmytryshyn@globallogic.com> <1424713267.27930.250.camel@citrix.com> <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> X-Mailer: Evolution 3.12.9-1+b1 MIME-Version: 1.0 X-DLP: MIA1 Cc: Iurii Konovalenko , Keir Fraser , Tim Deegan , Oleksandr Dmytryshyn , Ian Jackson , xen-devel@lists.xen.org, embedded-pv-devel@lists.xenproject.org, Lars Kurth , Stefano Panella , Jan Beulich , Andrew Cooper , DarioFaggioli , PaulDurrant , =?ISO-8859-1?Q?RogerPauMonn=E9?= Subject: Re: [Embedded-pv-devel] [PATCH v7] sndif: add ABI for Para-virtual sound X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org On Thu, 2015-03-12 at 18:14 +0000, Lars Kurth wrote: > Hi,I nearly missed this. Please make sure you forward stuff and change > the headline if you want me to look into things. Otherwise I may miss > it. Sure, I'll try and remember. FYI before Ian J went away he mentioned that he had raised some questions/issues (either on this or a previous version) which had not yet been answered (or maybe not answered to his satisfaction, I'm not sure) but that if those were addressed he would take a look with a view to acking the interface for inclusion in xen.git. (I've not looked in the threads for it, so I don't know the exact state). > From my perspective, this exactly the kind of scenario why we created > the embedded / automotive subproject, with an option to store code in > repos owned by the project. > > Given that the primary use-case of these drivers is embedded / > automotive, my suggestion would be to > 1.a) Use a repo in the embedded / automotive pv driver subproject to > host the spec - but use a file system structure that matches the xen > tree > 1.b) I would assume there would be one back-end and several front-ends > for these drivers and some would eventually appear in trees owned by > the embedded / automotive pv driver subproject > > In this case, the maintainer responsibility would fall to members of > the embedded / automotive pv driver subproject. Once there are several > implementations, and enough people with skills to review we can > re-visit where the spec and drivers live. > > We can have a discussion about criteria of when to move, but I don't > think that makes a lot of sense. I think the concerns that need to be > addressed are: > 2.a) Enough skills to review the code / protocols from different > stake-holders - this should happen with time, once the spec and code > are there. And of course once the embedded / automotive pv driver > subproject graduates, that will also give extra weight to its > maintainers in the wider community > 2.b) Of course if there was a strong case that PV sound drivers are > extremely useful for core data centre use-cases, I would probably > suggest another approach > > Maybe 2.b) needs to be checked with Intel folks - there may be some > sound requirement for XenGT > > Would this work as a way forward? I think the main things which is missing is some decision as to the the point at which we would consider the ABI for a PV protocol fixed, i.e. to be maintained in a backwards compatible manner from then on. That's of particular importance when one end of the pair is implemented in external projects (e.g. OS driver frontends). If the interface is not declared stable then changes would be allowed which would invalidate those drivers. Ian. _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 17 13:05:10 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 17 Mar 2015 13:05:10 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXrBG-0006eL-Dp; Tue, 17 Mar 2015 13:05:10 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXrBF-0006e2-01 for embedded-pv-devel@lists.xenproject.org; Tue, 17 Mar 2015 13:05:09 +0000 Received: from [85.158.139.211] by server-2.bemta-5.messagelabs.com id 44/26-18732-48628055; Tue, 17 Mar 2015 13:05:08 +0000 X-Env-Sender: lars.kurth.xen@gmail.com X-Msg-Ref: server-16.tower-206.messagelabs.com!1426597507!8371384!1 X-Originating-IP: [209.85.212.174] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 25390 invoked from network); 17 Mar 2015 13:05:07 -0000 Received: from mail-wi0-f174.google.com (HELO mail-wi0-f174.google.com) (209.85.212.174) by server-16.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 17 Mar 2015 13:05:07 -0000 Received: by wibdy8 with SMTP id dy8so62656578wib.0 for ; Tue, 17 Mar 2015 06:05:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=422j8wSjrDdlcmoUwAX6NpICkCP/6OTGQZG37tsK4xc=; b=uSlWy2tJWgR+FW7RiKrWv6BDFSnEpiC5V9gNm6SPpKHtGyAVnakGvXkD6slygJEoAh UccjWtwnp6/k8L2ahRcpaFC02uHIkfWA3xwsa4cf5qqGy/7GNS4yV+yy9fnp6K2KlUxj 2pOGPV96QgpJSAMBAFE6JW/nUv4n2Gre34e6r9MXk7FEtVeYHRY/iK6UsSEUZ5rf4oX0 8Hjwl96ZbVGg277BIyzL8ZiO/a99XyWvB4q5xIFzxDhWspP/MHwzJ4ZVGEUnMPNyXbxf Gu0dcWlfXOqkBQDWxqsmMpCgNX3dzGBBLD94uKcVhq9v4CvpRutyEbiVzFjNjiqolwVp Wk5w== X-Received: by 10.194.110.233 with SMTP id id9mr133110996wjb.136.1426597507333; Tue, 17 Mar 2015 06:05:07 -0700 (PDT) Received: from [192.168.0.12] (97e5522d.skybroadband.com. [151.229.82.45]) by mx.google.com with ESMTPSA id gt4sm2608009wib.21.2015.03.17.06.05.05 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 17 Mar 2015 06:05:06 -0700 (PDT) Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) From: Lars Kurth In-Reply-To: <1426592445.18247.198.camel@citrix.com> Date: Tue, 17 Mar 2015 13:05:04 +0000 Message-Id: References: <1423222117-18949-1-git-send-email-oleksandr.dmytryshyn@globallogic.com> <1424713267.27930.250.camel@citrix.com> <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> <1426592445.18247.198.camel@citrix.com> To: Ian Campbell X-Mailer: Apple Mail (2.2070.6) Cc: Iurii Konovalenko , Keir Fraser , Tim Deegan , Oleksandr Dmytryshyn , Ian Jackson , xen-devel , embedded-pv-devel@lists.xenproject.org, Lars Kurth , Stefano Panella , Jan Beulich , Andrew Cooper , DarioFaggioli , PaulDurrant , =?utf-8?Q?RogerPauMonn=C3=A9?= Subject: Re: [Embedded-pv-devel] [PATCH v7] sndif: add ABI for Para-virtual sound X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org > On 17 Mar 2015, at 11:40, Ian Campbell wrote: > > On Thu, 2015-03-12 at 18:14 +0000, Lars Kurth wrote: >> Hi,I nearly missed this. Please make sure you forward stuff and change >> the headline if you want me to look into things. Otherwise I may miss >> it. > > Sure, I'll try and remember. > > FYI before Ian J went away he mentioned that he had raised some > questions/issues (either on this or a previous version) which had not > yet been answered (or maybe not answered to his satisfaction, I'm not > sure) but that if those were addressed he would take a look with a view > to acking the interface for inclusion in xen.git. OK. So this means there are some concrete lose ends, which need to be followed up on. I also remember that there was a discussion on how we should specify protocols, which does not appear to have fully concluded either. >> >> Would this work as a way forward? > > I think the main things which is missing is some decision as to the the > point at which we would consider the ABI for a PV protocol fixed, i.e. > to be maintained in a backwards compatible manner from then on. What do we do with new APIs in such situations? It would appear that there is some commonality in how we would handle a protocols and an API. I am assuming APIs such as new hypercalls don't immediately become fixed and backwards compatible. > That's of particular importance when one end of the pair is implemented > in external projects (e.g. OS driver frontends). If the interface is not > declared stable then changes would be allowed which would invalidate > those drivers. I understand that external projects may have different rules to us, which may cause problems. If this was the case in this instance, this would be an argument for using a xen project tree as a temporary location until we have declared the protocol ABI stable. Regards Lars _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 17 13:05:10 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 17 Mar 2015 13:05:10 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXrBG-0006eL-Dp; Tue, 17 Mar 2015 13:05:10 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXrBF-0006e2-01 for embedded-pv-devel@lists.xenproject.org; Tue, 17 Mar 2015 13:05:09 +0000 Received: from [85.158.139.211] by server-2.bemta-5.messagelabs.com id 44/26-18732-48628055; Tue, 17 Mar 2015 13:05:08 +0000 X-Env-Sender: lars.kurth.xen@gmail.com X-Msg-Ref: server-16.tower-206.messagelabs.com!1426597507!8371384!1 X-Originating-IP: [209.85.212.174] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 25390 invoked from network); 17 Mar 2015 13:05:07 -0000 Received: from mail-wi0-f174.google.com (HELO mail-wi0-f174.google.com) (209.85.212.174) by server-16.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 17 Mar 2015 13:05:07 -0000 Received: by wibdy8 with SMTP id dy8so62656578wib.0 for ; Tue, 17 Mar 2015 06:05:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=422j8wSjrDdlcmoUwAX6NpICkCP/6OTGQZG37tsK4xc=; b=uSlWy2tJWgR+FW7RiKrWv6BDFSnEpiC5V9gNm6SPpKHtGyAVnakGvXkD6slygJEoAh UccjWtwnp6/k8L2ahRcpaFC02uHIkfWA3xwsa4cf5qqGy/7GNS4yV+yy9fnp6K2KlUxj 2pOGPV96QgpJSAMBAFE6JW/nUv4n2Gre34e6r9MXk7FEtVeYHRY/iK6UsSEUZ5rf4oX0 8Hjwl96ZbVGg277BIyzL8ZiO/a99XyWvB4q5xIFzxDhWspP/MHwzJ4ZVGEUnMPNyXbxf Gu0dcWlfXOqkBQDWxqsmMpCgNX3dzGBBLD94uKcVhq9v4CvpRutyEbiVzFjNjiqolwVp Wk5w== X-Received: by 10.194.110.233 with SMTP id id9mr133110996wjb.136.1426597507333; Tue, 17 Mar 2015 06:05:07 -0700 (PDT) Received: from [192.168.0.12] (97e5522d.skybroadband.com. [151.229.82.45]) by mx.google.com with ESMTPSA id gt4sm2608009wib.21.2015.03.17.06.05.05 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 17 Mar 2015 06:05:06 -0700 (PDT) Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) From: Lars Kurth In-Reply-To: <1426592445.18247.198.camel@citrix.com> Date: Tue, 17 Mar 2015 13:05:04 +0000 Message-Id: References: <1423222117-18949-1-git-send-email-oleksandr.dmytryshyn@globallogic.com> <1424713267.27930.250.camel@citrix.com> <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> <1426592445.18247.198.camel@citrix.com> To: Ian Campbell X-Mailer: Apple Mail (2.2070.6) Cc: Iurii Konovalenko , Keir Fraser , Tim Deegan , Oleksandr Dmytryshyn , Ian Jackson , xen-devel , embedded-pv-devel@lists.xenproject.org, Lars Kurth , Stefano Panella , Jan Beulich , Andrew Cooper , DarioFaggioli , PaulDurrant , =?utf-8?Q?RogerPauMonn=C3=A9?= Subject: Re: [Embedded-pv-devel] [PATCH v7] sndif: add ABI for Para-virtual sound X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org > On 17 Mar 2015, at 11:40, Ian Campbell wrote: > > On Thu, 2015-03-12 at 18:14 +0000, Lars Kurth wrote: >> Hi,I nearly missed this. Please make sure you forward stuff and change >> the headline if you want me to look into things. Otherwise I may miss >> it. > > Sure, I'll try and remember. > > FYI before Ian J went away he mentioned that he had raised some > questions/issues (either on this or a previous version) which had not > yet been answered (or maybe not answered to his satisfaction, I'm not > sure) but that if those were addressed he would take a look with a view > to acking the interface for inclusion in xen.git. OK. So this means there are some concrete lose ends, which need to be followed up on. I also remember that there was a discussion on how we should specify protocols, which does not appear to have fully concluded either. >> >> Would this work as a way forward? > > I think the main things which is missing is some decision as to the the > point at which we would consider the ABI for a PV protocol fixed, i.e. > to be maintained in a backwards compatible manner from then on. What do we do with new APIs in such situations? It would appear that there is some commonality in how we would handle a protocols and an API. I am assuming APIs such as new hypercalls don't immediately become fixed and backwards compatible. > That's of particular importance when one end of the pair is implemented > in external projects (e.g. OS driver frontends). If the interface is not > declared stable then changes would be allowed which would invalidate > those drivers. I understand that external projects may have different rules to us, which may cause problems. If this was the case in this instance, this would be an argument for using a xen project tree as a temporary location until we have declared the protocol ABI stable. Regards Lars _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 17 13:54:27 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 17 Mar 2015 13:54:27 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXrwx-0004gK-Di; Tue, 17 Mar 2015 13:54:27 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXrwv-0004fy-Ry for embedded-pv-devel@lists.xenproject.org; Tue, 17 Mar 2015 13:54:25 +0000 Received: from [85.158.139.211] by server-17.bemta-5.messagelabs.com id AE/5C-14924-11238055; Tue, 17 Mar 2015 13:54:25 +0000 X-Env-Sender: JBeulich@suse.com X-Msg-Ref: server-4.tower-206.messagelabs.com!1426600464!11290883!1 X-Originating-IP: [130.57.118.101] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 13255 invoked from network); 17 Mar 2015 13:54:24 -0000 Received: from mail.emea.novell.com (HELO mail.emea.novell.com) (130.57.118.101) by server-4.tower-206.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 17 Mar 2015 13:54:24 -0000 Received: from EMEA1-MTA by mail.emea.novell.com with Novell_GroupWise; Tue, 17 Mar 2015 13:54:23 +0000 Message-Id: <5508401C020000780006ADDE@mail.emea.novell.com> X-Mailer: Novell GroupWise Internet Agent 14.0.1 Date: Tue, 17 Mar 2015 13:54:20 +0000 From: "Jan Beulich" To: "Lars Kurth" References: <1423222117-18949-1-git-send-email-oleksandr.dmytryshyn@globallogic.com> <1424713267.27930.250.camel@citrix.com> <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> <1426592445.18247.198.camel@citrix.com> In-Reply-To: Mime-Version: 1.0 Content-Disposition: inline Cc: Tim Deegan , Iurii Konovalenko , Keir Fraser , Ian Campbell , Andrew Cooper , DarioFaggioli , Ian Jackson , xen-devel , embedded-pv-devel@lists.xenproject.org, PaulDurrant , Stefano Panella , Oleksandr Dmytryshyn , Lars Kurth , roger.pau@citrix.com Subject: Re: [Embedded-pv-devel] [PATCH v7] sndif: add ABI for Para-virtual sound X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org >>> On 17.03.15 at 14:05, wrote: >> On 17 Mar 2015, at 11:40, Ian Campbell wrote: >> I think the main things which is missing is some decision as to the the >> point at which we would consider the ABI for a PV protocol fixed, i.e. >> to be maintained in a backwards compatible manner from then on. > > What do we do with new APIs in such situations? It would appear that there > is some commonality in how we would handle a protocols and an API. I am > assuming APIs such as new hypercalls don't immediately become fixed and > backwards compatible. New hypercalls become set in stone as soon as they appear in any released version, unless specifically marked as experimental or alike. The situation is quite different for a protocol specification like this: Here we talk about something where no code would live in xen.git at all, only the abstract description. Hence its stability can't usefully be tied to any released Xen version. Jan _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 17 13:54:27 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 17 Mar 2015 13:54:27 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXrwx-0004gK-Di; Tue, 17 Mar 2015 13:54:27 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXrwv-0004fy-Ry for embedded-pv-devel@lists.xenproject.org; Tue, 17 Mar 2015 13:54:25 +0000 Received: from [85.158.139.211] by server-17.bemta-5.messagelabs.com id AE/5C-14924-11238055; Tue, 17 Mar 2015 13:54:25 +0000 X-Env-Sender: JBeulich@suse.com X-Msg-Ref: server-4.tower-206.messagelabs.com!1426600464!11290883!1 X-Originating-IP: [130.57.118.101] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 13255 invoked from network); 17 Mar 2015 13:54:24 -0000 Received: from mail.emea.novell.com (HELO mail.emea.novell.com) (130.57.118.101) by server-4.tower-206.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 17 Mar 2015 13:54:24 -0000 Received: from EMEA1-MTA by mail.emea.novell.com with Novell_GroupWise; Tue, 17 Mar 2015 13:54:23 +0000 Message-Id: <5508401C020000780006ADDE@mail.emea.novell.com> X-Mailer: Novell GroupWise Internet Agent 14.0.1 Date: Tue, 17 Mar 2015 13:54:20 +0000 From: "Jan Beulich" To: "Lars Kurth" References: <1423222117-18949-1-git-send-email-oleksandr.dmytryshyn@globallogic.com> <1424713267.27930.250.camel@citrix.com> <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> <1426592445.18247.198.camel@citrix.com> In-Reply-To: Mime-Version: 1.0 Content-Disposition: inline Cc: Tim Deegan , Iurii Konovalenko , Keir Fraser , Ian Campbell , Andrew Cooper , DarioFaggioli , Ian Jackson , xen-devel , embedded-pv-devel@lists.xenproject.org, PaulDurrant , Stefano Panella , Oleksandr Dmytryshyn , Lars Kurth , roger.pau@citrix.com Subject: Re: [Embedded-pv-devel] [PATCH v7] sndif: add ABI for Para-virtual sound X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org >>> On 17.03.15 at 14:05, wrote: >> On 17 Mar 2015, at 11:40, Ian Campbell wrote: >> I think the main things which is missing is some decision as to the the >> point at which we would consider the ABI for a PV protocol fixed, i.e. >> to be maintained in a backwards compatible manner from then on. > > What do we do with new APIs in such situations? It would appear that there > is some commonality in how we would handle a protocols and an API. I am > assuming APIs such as new hypercalls don't immediately become fixed and > backwards compatible. New hypercalls become set in stone as soon as they appear in any released version, unless specifically marked as experimental or alike. The situation is quite different for a protocol specification like this: Here we talk about something where no code would live in xen.git at all, only the abstract description. Hence its stability can't usefully be tied to any released Xen version. Jan _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 17 14:00:13 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 17 Mar 2015 14:00:13 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXs2W-00058h-T0; Tue, 17 Mar 2015 14:00:12 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXs2V-00058W-1b for embedded-pv-devel@lists.xenproject.org; Tue, 17 Mar 2015 14:00:11 +0000 Received: from [85.158.137.68] by server-17.bemta-3.messagelabs.com id E4/59-09011-A6338055; Tue, 17 Mar 2015 14:00:10 +0000 X-Env-Sender: Ian.Campbell@citrix.com X-Msg-Ref: server-2.tower-31.messagelabs.com!1426600806!12942690!1 X-Originating-IP: [66.165.176.89] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni44OSA9PiAyMDMwMDc=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 13870 invoked from network); 17 Mar 2015 14:00:07 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-2.tower-31.messagelabs.com with RC4-SHA encrypted SMTP; 17 Mar 2015 14:00:07 -0000 X-IronPort-AV: E=Sophos;i="5.11,416,1422921600"; d="scan'208";a="244163102" Message-ID: <1426600774.18247.236.camel@citrix.com> From: Ian Campbell To: Lars Kurth Date: Tue, 17 Mar 2015 13:59:34 +0000 In-Reply-To: References: <1423222117-18949-1-git-send-email-oleksandr.dmytryshyn@globallogic.com> <1424713267.27930.250.camel@citrix.com> <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> <1426592445.18247.198.camel@citrix.com> X-Mailer: Evolution 3.12.9-1+b1 MIME-Version: 1.0 X-DLP: MIA2 Cc: Iurii Konovalenko , Keir Fraser , Tim Deegan , Oleksandr Dmytryshyn , Ian Jackson , xen-devel , embedded-pv-devel@lists.xenproject.org, Lars Kurth , Stefano Panella , Jan Beulich , Andrew Cooper , DarioFaggioli , PaulDurrant , =?ISO-8859-1?Q?RogerPauMonn=E9?= Subject: Re: [Embedded-pv-devel] [Xen-devel] [PATCH v7] sndif: add ABI for Para-virtual sound X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org On Tue, 2015-03-17 at 13:05 +0000, Lars Kurth wrote: > > On 17 Mar 2015, at 11:40, Ian Campbell wrote: > > > > On Thu, 2015-03-12 at 18:14 +0000, Lars Kurth wrote: > >> Hi,I nearly missed this. Please make sure you forward stuff and change > >> the headline if you want me to look into things. Otherwise I may miss > >> it. > > > > Sure, I'll try and remember. > > > > FYI before Ian J went away he mentioned that he had raised some > > questions/issues (either on this or a previous version) which had not > > yet been answered (or maybe not answered to his satisfaction, I'm not > > sure) but that if those were addressed he would take a look with a view > > to acking the interface for inclusion in xen.git. > > OK. So this means there are some concrete lose ends, which need to be followed up on. I also remember that there was a discussion on how we should specify protocols, which does not appear to have fully concluded either. > > >> > >> Would this work as a way forward? > > > > I think the main things which is missing is some decision as to the the > > point at which we would consider the ABI for a PV protocol fixed, i.e. > > to be maintained in a backwards compatible manner from then on. > > What do we do with new APIs in such situations? We review then carefully and hope we get them right. We manage to get this right at least some of the time because many of us are familiar with the issues WRT e.g. memory management hypercalls. This is what I was getting at with "people are naturally a bit cautious about creating new ABIs, which must be maintained long term, for types of device with which they are not really familiar." in my initial mail. The "which they are not really familiar" is pretty key. It's also (normally) not too hard to add a new hypercall fixing a shortcoming in an existing one while retaining backwards compat, compared with doing that for an I/O protocol (see: netchannel2). In the I/O case adding extensions also is reasonably well understood and something we manage, but fixing a core issue is much harder (see: the non-uniformity of the blk protocol over different architectures, or the ring space wastage due to various power of two requirements, neither of which can realistically be properly fixed). Ian. _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 17 14:00:13 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 17 Mar 2015 14:00:13 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXs2W-00058h-T0; Tue, 17 Mar 2015 14:00:12 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXs2V-00058W-1b for embedded-pv-devel@lists.xenproject.org; Tue, 17 Mar 2015 14:00:11 +0000 Received: from [85.158.137.68] by server-17.bemta-3.messagelabs.com id E4/59-09011-A6338055; Tue, 17 Mar 2015 14:00:10 +0000 X-Env-Sender: Ian.Campbell@citrix.com X-Msg-Ref: server-2.tower-31.messagelabs.com!1426600806!12942690!1 X-Originating-IP: [66.165.176.89] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni44OSA9PiAyMDMwMDc=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 13870 invoked from network); 17 Mar 2015 14:00:07 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-2.tower-31.messagelabs.com with RC4-SHA encrypted SMTP; 17 Mar 2015 14:00:07 -0000 X-IronPort-AV: E=Sophos;i="5.11,416,1422921600"; d="scan'208";a="244163102" Message-ID: <1426600774.18247.236.camel@citrix.com> From: Ian Campbell To: Lars Kurth Date: Tue, 17 Mar 2015 13:59:34 +0000 In-Reply-To: References: <1423222117-18949-1-git-send-email-oleksandr.dmytryshyn@globallogic.com> <1424713267.27930.250.camel@citrix.com> <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> <1426592445.18247.198.camel@citrix.com> X-Mailer: Evolution 3.12.9-1+b1 MIME-Version: 1.0 X-DLP: MIA2 Cc: Iurii Konovalenko , Keir Fraser , Tim Deegan , Oleksandr Dmytryshyn , Ian Jackson , xen-devel , embedded-pv-devel@lists.xenproject.org, Lars Kurth , Stefano Panella , Jan Beulich , Andrew Cooper , DarioFaggioli , PaulDurrant , =?ISO-8859-1?Q?RogerPauMonn=E9?= Subject: Re: [Embedded-pv-devel] [Xen-devel] [PATCH v7] sndif: add ABI for Para-virtual sound X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org On Tue, 2015-03-17 at 13:05 +0000, Lars Kurth wrote: > > On 17 Mar 2015, at 11:40, Ian Campbell wrote: > > > > On Thu, 2015-03-12 at 18:14 +0000, Lars Kurth wrote: > >> Hi,I nearly missed this. Please make sure you forward stuff and change > >> the headline if you want me to look into things. Otherwise I may miss > >> it. > > > > Sure, I'll try and remember. > > > > FYI before Ian J went away he mentioned that he had raised some > > questions/issues (either on this or a previous version) which had not > > yet been answered (or maybe not answered to his satisfaction, I'm not > > sure) but that if those were addressed he would take a look with a view > > to acking the interface for inclusion in xen.git. > > OK. So this means there are some concrete lose ends, which need to be followed up on. I also remember that there was a discussion on how we should specify protocols, which does not appear to have fully concluded either. > > >> > >> Would this work as a way forward? > > > > I think the main things which is missing is some decision as to the the > > point at which we would consider the ABI for a PV protocol fixed, i.e. > > to be maintained in a backwards compatible manner from then on. > > What do we do with new APIs in such situations? We review then carefully and hope we get them right. We manage to get this right at least some of the time because many of us are familiar with the issues WRT e.g. memory management hypercalls. This is what I was getting at with "people are naturally a bit cautious about creating new ABIs, which must be maintained long term, for types of device with which they are not really familiar." in my initial mail. The "which they are not really familiar" is pretty key. It's also (normally) not too hard to add a new hypercall fixing a shortcoming in an existing one while retaining backwards compat, compared with doing that for an I/O protocol (see: netchannel2). In the I/O case adding extensions also is reasonably well understood and something we manage, but fixing a core issue is much harder (see: the non-uniformity of the blk protocol over different architectures, or the ring space wastage due to various power of two requirements, neither of which can realistically be properly fixed). Ian. _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 17 14:13:54 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 17 Mar 2015 14:13:54 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXsFm-0007UW-Pm; Tue, 17 Mar 2015 14:13:54 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXrDT-0006su-7O for embedded-pv-devel@lists.xenproject.org; Tue, 17 Mar 2015 13:07:27 +0000 Received: from [85.158.139.211] by server-10.bemta-5.messagelabs.com id BE/87-14739-E0728055; Tue, 17 Mar 2015 13:07:26 +0000 X-Env-Sender: Stefano.Stabellini@citrix.com X-Msg-Ref: server-7.tower-206.messagelabs.com!1426597644!11296439!1 X-Originating-IP: [66.165.176.89] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni44OSA9PiAyMDMwMDc=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 25653 invoked from network); 17 Mar 2015 13:07:25 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-7.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 17 Mar 2015 13:07:25 -0000 X-IronPort-AV: E=Sophos;i="5.11,416,1422921600"; d="scan'208";a="244137045" Date: Tue, 17 Mar 2015 13:05:20 +0000 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Ian Campbell In-Reply-To: <1426592445.18247.198.camel@citrix.com> Message-ID: References: <1423222117-18949-1-git-send-email-oleksandr.dmytryshyn@globallogic.com> <1424713267.27930.250.camel@citrix.com> <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> <1426592445.18247.198.camel@citrix.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 X-DLP: MIA1 X-Mailman-Approved-At: Tue, 17 Mar 2015 14:13:53 +0000 Cc: Iurii Konovalenko , Keir Fraser , Lars Kurth , Ian Jackson , Oleksandr Dmytryshyn , Tim Deegan , xen-devel@lists.xen.org, embedded-pv-devel@lists.xenproject.org, Lars Kurth , Stefano Panella , Jan Beulich , Andrew Cooper , DarioFaggioli , PaulDurrant , =?UTF-8?Q?RogerPauMonn=C3=A9?= Subject: Re: [Embedded-pv-devel] [Xen-devel] [PATCH v7] sndif: add ABI for Para-virtual sound X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org On Tue, 17 Mar 2015, Ian Campbell wrote: > On Thu, 2015-03-12 at 18:14 +0000, Lars Kurth wrote: > > Hi,I nearly missed this. Please make sure you forward stuff and change > > the headline if you want me to look into things. Otherwise I may miss > > it. > > Sure, I'll try and remember. > > FYI before Ian J went away he mentioned that he had raised some > questions/issues (either on this or a previous version) which had not > yet been answered (or maybe not answered to his satisfaction, I'm not > sure) but that if those were addressed he would take a look with a view > to acking the interface for inclusion in xen.git. > > (I've not looked in the threads for it, so I don't know the exact > state). > > > From my perspective, this exactly the kind of scenario why we created > > the embedded / automotive subproject, with an option to store code in > > repos owned by the project. > > > > Given that the primary use-case of these drivers is embedded / > > automotive, my suggestion would be to > > 1.a) Use a repo in the embedded / automotive pv driver subproject to > > host the spec - but use a file system structure that matches the xen > > tree > > 1.b) I would assume there would be one back-end and several front-ends > > for these drivers and some would eventually appear in trees owned by > > the embedded / automotive pv driver subproject > > > > In this case, the maintainer responsibility would fall to members of > > the embedded / automotive pv driver subproject. Once there are several > > implementations, and enough people with skills to review we can > > re-visit where the spec and drivers live. > > > > We can have a discussion about criteria of when to move, but I don't > > think that makes a lot of sense. I think the concerns that need to be > > addressed are: > > 2.a) Enough skills to review the code / protocols from different > > stake-holders - this should happen with time, once the spec and code > > are there. And of course once the embedded / automotive pv driver > > subproject graduates, that will also give extra weight to its > > maintainers in the wider community > > 2.b) Of course if there was a strong case that PV sound drivers are > > extremely useful for core data centre use-cases, I would probably > > suggest another approach > > > > Maybe 2.b) needs to be checked with Intel folks - there may be some > > sound requirement for XenGT > > > > Would this work as a way forward? > > I think the main things which is missing is some decision as to the the > point at which we would consider the ABI for a PV protocol fixed, i.e. > to be maintained in a backwards compatible manner from then on. > > That's of particular importance when one end of the pair is implemented > in external projects (e.g. OS driver frontends). If the interface is not > declared stable then changes would be allowed which would invalidate > those drivers. I think that you are right. Declaring the interface stable or unstable is far more important than where the code or the spec lives. If we formally specified within the spec that the ABI is not maintained for backward compatibility, the bar for acceptance in xen-unstable would be far lower. Maybe the spec could even be accepted as is if nobody has any comments? _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 17 14:13:54 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 17 Mar 2015 14:13:54 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXsFm-0007UW-Pm; Tue, 17 Mar 2015 14:13:54 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YXrDT-0006su-7O for embedded-pv-devel@lists.xenproject.org; Tue, 17 Mar 2015 13:07:27 +0000 Received: from [85.158.139.211] by server-10.bemta-5.messagelabs.com id BE/87-14739-E0728055; Tue, 17 Mar 2015 13:07:26 +0000 X-Env-Sender: Stefano.Stabellini@citrix.com X-Msg-Ref: server-7.tower-206.messagelabs.com!1426597644!11296439!1 X-Originating-IP: [66.165.176.89] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni44OSA9PiAyMDMwMDc=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 25653 invoked from network); 17 Mar 2015 13:07:25 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-7.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 17 Mar 2015 13:07:25 -0000 X-IronPort-AV: E=Sophos;i="5.11,416,1422921600"; d="scan'208";a="244137045" Date: Tue, 17 Mar 2015 13:05:20 +0000 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Ian Campbell In-Reply-To: <1426592445.18247.198.camel@citrix.com> Message-ID: References: <1423222117-18949-1-git-send-email-oleksandr.dmytryshyn@globallogic.com> <1424713267.27930.250.camel@citrix.com> <45BD1410-1291-412C-86C3-CBB36CABBB1B@gmail.com> <1426592445.18247.198.camel@citrix.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 X-DLP: MIA1 X-Mailman-Approved-At: Tue, 17 Mar 2015 14:13:53 +0000 Cc: Iurii Konovalenko , Keir Fraser , Lars Kurth , Ian Jackson , Oleksandr Dmytryshyn , Tim Deegan , xen-devel@lists.xen.org, embedded-pv-devel@lists.xenproject.org, Lars Kurth , Stefano Panella , Jan Beulich , Andrew Cooper , DarioFaggioli , PaulDurrant , =?UTF-8?Q?RogerPauMonn=C3=A9?= Subject: Re: [Embedded-pv-devel] [Xen-devel] [PATCH v7] sndif: add ABI for Para-virtual sound X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org On Tue, 17 Mar 2015, Ian Campbell wrote: > On Thu, 2015-03-12 at 18:14 +0000, Lars Kurth wrote: > > Hi,I nearly missed this. Please make sure you forward stuff and change > > the headline if you want me to look into things. Otherwise I may miss > > it. > > Sure, I'll try and remember. > > FYI before Ian J went away he mentioned that he had raised some > questions/issues (either on this or a previous version) which had not > yet been answered (or maybe not answered to his satisfaction, I'm not > sure) but that if those were addressed he would take a look with a view > to acking the interface for inclusion in xen.git. > > (I've not looked in the threads for it, so I don't know the exact > state). > > > From my perspective, this exactly the kind of scenario why we created > > the embedded / automotive subproject, with an option to store code in > > repos owned by the project. > > > > Given that the primary use-case of these drivers is embedded / > > automotive, my suggestion would be to > > 1.a) Use a repo in the embedded / automotive pv driver subproject to > > host the spec - but use a file system structure that matches the xen > > tree > > 1.b) I would assume there would be one back-end and several front-ends > > for these drivers and some would eventually appear in trees owned by > > the embedded / automotive pv driver subproject > > > > In this case, the maintainer responsibility would fall to members of > > the embedded / automotive pv driver subproject. Once there are several > > implementations, and enough people with skills to review we can > > re-visit where the spec and drivers live. > > > > We can have a discussion about criteria of when to move, but I don't > > think that makes a lot of sense. I think the concerns that need to be > > addressed are: > > 2.a) Enough skills to review the code / protocols from different > > stake-holders - this should happen with time, once the spec and code > > are there. And of course once the embedded / automotive pv driver > > subproject graduates, that will also give extra weight to its > > maintainers in the wider community > > 2.b) Of course if there was a strong case that PV sound drivers are > > extremely useful for core data centre use-cases, I would probably > > suggest another approach > > > > Maybe 2.b) needs to be checked with Intel folks - there may be some > > sound requirement for XenGT > > > > Would this work as a way forward? > > I think the main things which is missing is some decision as to the the > point at which we would consider the ABI for a PV protocol fixed, i.e. > to be maintained in a backwards compatible manner from then on. > > That's of particular importance when one end of the pair is implemented > in external projects (e.g. OS driver frontends). If the interface is not > declared stable then changes would be allowed which would invalidate > those drivers. I think that you are right. Declaring the interface stable or unstable is far more important than where the code or the spec lives. If we formally specified within the spec that the ABI is not maintained for backward compatibility, the bar for acceptance in xen-unstable would be far lower. Maybe the spec could even be accepted as is if nobody has any comments? _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Wed Mar 18 17:23:59 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Wed, 18 Mar 2015 17:23:59 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYHhG-0000OD-Om; Wed, 18 Mar 2015 17:23:58 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYHhE-0000N6-Dc for Embedded-pv-devel@lists.xenproject.org; Wed, 18 Mar 2015 17:23:56 +0000 Received: from [85.158.139.211] by server-12.bemta-5.messagelabs.com id 46/4D-14925-BA4B9055; Wed, 18 Mar 2015 17:23:55 +0000 X-Env-Sender: iurii.konovalenko@globallogic.com X-Msg-Ref: server-14.tower-206.messagelabs.com!1426699432!6235591!1 X-Originating-IP: [64.18.0.189] X-SpamReason: No, hits=0.3 required=7.0 tests=RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 32027 invoked from network); 18 Mar 2015 17:23:54 -0000 Received: from exprod5og119.obsmtp.com (HELO exprod5og119.obsmtp.com) (64.18.0.189) by server-14.tower-206.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 18 Mar 2015 17:23:54 -0000 Received: from mail-ie0-f181.google.com ([209.85.223.181]) (using TLSv1) by exprod5ob119.postini.com ([64.18.4.12]) with SMTP ID DSNKVQm0qGvY1PREGnqIEUY4HRlm4W/fALF9@postini.com; Wed, 18 Mar 2015 10:23:54 PDT Received: by iegc3 with SMTP id c3so44803222ieg.3 for ; Wed, 18 Mar 2015 10:23:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:date:message-id:subject:from:to:content-type; bh=SG+q25LLuWIu4qd6FkwvzpfAwiWtsK0P1JZa8cxhoIs=; b=GVjYnJAYw84J/teOMnWdREqqAStxLvgBqx7tN00+1OWp2gNo0nizJS7gv5ulIHEbD5 cZvy8Dwt9fGziKfaFt4fDYbFlr/oiH/18x1qCLMolQ5Wb5LeJ3JEpR+tFt2GfhQGbyAh 2QNAuFKB9vxRIwnMkvES1Rhvyy5/uJ1ZyAAz4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:date:message-id:subject:from:to :content-type; bh=SG+q25LLuWIu4qd6FkwvzpfAwiWtsK0P1JZa8cxhoIs=; b=PrlkvQCLRXE0N+mqvMIYSiZta9nNUWi4gm6OOjiAKiIetWy+Nwl3+qJ8iLjSCMCTdB dSW8GxTcdI8A4EtVEhESfQviSxMbsTQso7KiDwXy7bfQreJo2VB4B1Y1VwdJUiBaDkMl PC6zDo/yOcyVE+3fqAAIf9VqrYIPdxMgnze/Vh6MVWHb5ztj03qBrWeL+uHC9NF9ua44 eN0X48k7gShOaHb0UeQSUVZx0LZI9Ke6Q0QYNGm/Jh5eNry7KcJhWHq+B3Y9yAi3Z711 8GmjOhItzWOKJOHUnC0HEsHYd6K0mpRd1wDxo2mawHFPdaVwlTZxQkNG67exUUtH9EsF xeaA== X-Gm-Message-State: ALoCoQkh4Wiq2lYVqlEtiq0lH7yShMKxM8AVLdwROLOk2xUjL0oVj6V4hh5Yw9FL2/pblU1EuvzlMEP/dUBwohlpPtOBbUvD9CICtmUMyoH6gcBb5fPzz8S4fpM+Y5mh/vJEbDLsLehGaG+u2Pf8KCOYsgxvX3wjATJ7NXJcdqKzTN9UTSYIxFg= X-Received: by 10.107.29.21 with SMTP id d21mr1814545iod.11.1426699432216; Wed, 18 Mar 2015 10:23:52 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.107.29.21 with SMTP id d21mr1814503iod.11.1426699431996; Wed, 18 Mar 2015 10:23:51 -0700 (PDT) Received: by 10.36.48.137 with HTTP; Wed, 18 Mar 2015 10:23:51 -0700 (PDT) Date: Wed, 18 Mar 2015 19:23:51 +0200 Message-ID: From: Iurii Konovalenko To: "xen-devel@lists.xen.org" , Embedded-pv-devel@lists.xenproject.org Subject: [Embedded-pv-devel] Userspace PV backend hangs X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org Hi, guys! We continue bringing up System based on Xen hypervisor on Renesas Lager board. We started 4 domains: Dom0 (Linux 3.14), Driver Domain (Linux 3.14), Cluster Domain (Linux 3.14), and DomU (Tizen with 3.14 kernel). Each domain has 2 VCPUs (4 physical CPUs are up). Currently, we use Xen version 4.6-unstable. We've successfully brought up PVBLK and PVUSB - both backends and frontends of these PV drivers live in Kernel-space. But we have problems with PV drivers with backends, that live in user-space. For example, Audio backend application hangs in the middle of initialization. Same for other PV drivers. Investigation shows, that we have deadlock. It is example of source: if (!xs_watch(xsh, sndbk_params.reconnectpath, "")) return -1; xs_read(xsh, XBT_NULL, buf, NULL); xs_read() hangs because dev/xenbus is locked by watch thread, created in xs_watch(). xs_watch() creates thread, which locks dev/xenbus, and goes to sleep in xenbus frontend (ret = wait_event_interruptible(u->read_waitq,!list_empty(&u->read_buffers));) until someone wake up it. But nobody can wake it up. We tried to change value using utils (xenstore-write), but it helps only sometimes: sometimes it helps thread to wake up, sometimes that thread sleeps and does not wake up. Sometimes backend passes this place successfully, but hangs on next similar xs_watch() + xs_read() combination. One more important note is, that if we set watch from via tools (xenstore-watch) to the exactly same path, as in backend, and then change value with xenstore-write, we see prints from xenstore-watch, but xs_watch thread is still sleeping. Could you please suggest what can be reason of such behavior? May be you saw such behavior earlier? Best regards. Iurii Konovalenko | Senior Software Engineer GlobalLogic _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Wed Mar 18 17:23:59 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Wed, 18 Mar 2015 17:23:59 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYHhG-0000OD-Om; Wed, 18 Mar 2015 17:23:58 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYHhE-0000N6-Dc for Embedded-pv-devel@lists.xenproject.org; Wed, 18 Mar 2015 17:23:56 +0000 Received: from [85.158.139.211] by server-12.bemta-5.messagelabs.com id 46/4D-14925-BA4B9055; Wed, 18 Mar 2015 17:23:55 +0000 X-Env-Sender: iurii.konovalenko@globallogic.com X-Msg-Ref: server-14.tower-206.messagelabs.com!1426699432!6235591!1 X-Originating-IP: [64.18.0.189] X-SpamReason: No, hits=0.3 required=7.0 tests=RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 32027 invoked from network); 18 Mar 2015 17:23:54 -0000 Received: from exprod5og119.obsmtp.com (HELO exprod5og119.obsmtp.com) (64.18.0.189) by server-14.tower-206.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 18 Mar 2015 17:23:54 -0000 Received: from mail-ie0-f181.google.com ([209.85.223.181]) (using TLSv1) by exprod5ob119.postini.com ([64.18.4.12]) with SMTP ID DSNKVQm0qGvY1PREGnqIEUY4HRlm4W/fALF9@postini.com; Wed, 18 Mar 2015 10:23:54 PDT Received: by iegc3 with SMTP id c3so44803222ieg.3 for ; Wed, 18 Mar 2015 10:23:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:date:message-id:subject:from:to:content-type; bh=SG+q25LLuWIu4qd6FkwvzpfAwiWtsK0P1JZa8cxhoIs=; b=GVjYnJAYw84J/teOMnWdREqqAStxLvgBqx7tN00+1OWp2gNo0nizJS7gv5ulIHEbD5 cZvy8Dwt9fGziKfaFt4fDYbFlr/oiH/18x1qCLMolQ5Wb5LeJ3JEpR+tFt2GfhQGbyAh 2QNAuFKB9vxRIwnMkvES1Rhvyy5/uJ1ZyAAz4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:date:message-id:subject:from:to :content-type; bh=SG+q25LLuWIu4qd6FkwvzpfAwiWtsK0P1JZa8cxhoIs=; b=PrlkvQCLRXE0N+mqvMIYSiZta9nNUWi4gm6OOjiAKiIetWy+Nwl3+qJ8iLjSCMCTdB dSW8GxTcdI8A4EtVEhESfQviSxMbsTQso7KiDwXy7bfQreJo2VB4B1Y1VwdJUiBaDkMl PC6zDo/yOcyVE+3fqAAIf9VqrYIPdxMgnze/Vh6MVWHb5ztj03qBrWeL+uHC9NF9ua44 eN0X48k7gShOaHb0UeQSUVZx0LZI9Ke6Q0QYNGm/Jh5eNry7KcJhWHq+B3Y9yAi3Z711 8GmjOhItzWOKJOHUnC0HEsHYd6K0mpRd1wDxo2mawHFPdaVwlTZxQkNG67exUUtH9EsF xeaA== X-Gm-Message-State: ALoCoQkh4Wiq2lYVqlEtiq0lH7yShMKxM8AVLdwROLOk2xUjL0oVj6V4hh5Yw9FL2/pblU1EuvzlMEP/dUBwohlpPtOBbUvD9CICtmUMyoH6gcBb5fPzz8S4fpM+Y5mh/vJEbDLsLehGaG+u2Pf8KCOYsgxvX3wjATJ7NXJcdqKzTN9UTSYIxFg= X-Received: by 10.107.29.21 with SMTP id d21mr1814545iod.11.1426699432216; Wed, 18 Mar 2015 10:23:52 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.107.29.21 with SMTP id d21mr1814503iod.11.1426699431996; Wed, 18 Mar 2015 10:23:51 -0700 (PDT) Received: by 10.36.48.137 with HTTP; Wed, 18 Mar 2015 10:23:51 -0700 (PDT) Date: Wed, 18 Mar 2015 19:23:51 +0200 Message-ID: From: Iurii Konovalenko To: "xen-devel@lists.xen.org" , Embedded-pv-devel@lists.xenproject.org Subject: [Embedded-pv-devel] Userspace PV backend hangs X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org Hi, guys! We continue bringing up System based on Xen hypervisor on Renesas Lager board. We started 4 domains: Dom0 (Linux 3.14), Driver Domain (Linux 3.14), Cluster Domain (Linux 3.14), and DomU (Tizen with 3.14 kernel). Each domain has 2 VCPUs (4 physical CPUs are up). Currently, we use Xen version 4.6-unstable. We've successfully brought up PVBLK and PVUSB - both backends and frontends of these PV drivers live in Kernel-space. But we have problems with PV drivers with backends, that live in user-space. For example, Audio backend application hangs in the middle of initialization. Same for other PV drivers. Investigation shows, that we have deadlock. It is example of source: if (!xs_watch(xsh, sndbk_params.reconnectpath, "")) return -1; xs_read(xsh, XBT_NULL, buf, NULL); xs_read() hangs because dev/xenbus is locked by watch thread, created in xs_watch(). xs_watch() creates thread, which locks dev/xenbus, and goes to sleep in xenbus frontend (ret = wait_event_interruptible(u->read_waitq,!list_empty(&u->read_buffers));) until someone wake up it. But nobody can wake it up. We tried to change value using utils (xenstore-write), but it helps only sometimes: sometimes it helps thread to wake up, sometimes that thread sleeps and does not wake up. Sometimes backend passes this place successfully, but hangs on next similar xs_watch() + xs_read() combination. One more important note is, that if we set watch from via tools (xenstore-watch) to the exactly same path, as in backend, and then change value with xenstore-write, we see prints from xenstore-watch, but xs_watch thread is still sleeping. Could you please suggest what can be reason of such behavior? May be you saw such behavior earlier? Best regards. Iurii Konovalenko | Senior Software Engineer GlobalLogic _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Thu Mar 19 10:38:39 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Thu, 19 Mar 2015 10:38:39 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYXqY-0003tQ-Qc; Thu, 19 Mar 2015 10:38:38 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYXqX-0003tC-BB for Embedded-pv-devel@lists.xenproject.org; Thu, 19 Mar 2015 10:38:37 +0000 Received: from [85.158.139.211] by server-8.bemta-5.messagelabs.com id A9/24-16789-C27AA055; Thu, 19 Mar 2015 10:38:36 +0000 X-Env-Sender: Ian.Campbell@citrix.com X-Msg-Ref: server-14.tower-206.messagelabs.com!1426761514!6400748!1 X-Originating-IP: [66.165.176.63] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni42MyA9PiAzMDYwNDg=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 15262 invoked from network); 19 Mar 2015 10:38:36 -0000 Received: from smtp02.citrix.com (HELO SMTP02.CITRIX.COM) (66.165.176.63) by server-14.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 19 Mar 2015 10:38:36 -0000 X-IronPort-AV: E=Sophos;i="5.11,429,1422921600"; d="scan'208";a="246496573" Message-ID: <1426761512.610.18.camel@citrix.com> From: Ian Campbell To: Marek =?ISO-8859-1?Q?Marczykowski-G=F3recki?= Date: Thu, 19 Mar 2015 10:38:32 +0000 In-Reply-To: <20150319011911.GA29029@mail-itl> References: <20150319011911.GA29029@mail-itl> X-Mailer: Evolution 3.12.9-1+b1 MIME-Version: 1.0 X-DLP: MIA1 Cc: Iurii Konovalenko , Embedded-pv-devel@lists.xenproject.org, Boris Ostrovsky , David Vrabel , xen-devel Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org T24gVGh1LCAyMDE1LTAzLTE5IGF0IDAyOjE5ICswMTAwLCBNYXJlayBNYXJjenlrb3dza2ktR8Oz cmVja2kgd3JvdGU6Cj4gSGksCj4gCj4gSSd2ZSBoaXQgc29tZSBkZWFkbG9jayBpbiBrZXJuZWwg eGVuc3RvcmUgY2xpZW50IGV4cG9zZWQgdmlhCj4gL3Byb2MveGVuL3hlbmJ1cy4KClNvdW5kcyBz aW1pbGFyIHRvIHdoYXQgSXVyaWkgYWxzbyByZXBvcnRlZCBsYXN0IG5pZ2h0IGluICJVc2Vyc3Bh Y2UgUFYKYmFja2VuZCBoYW5ncyIuCgpJdXJyaSdzIGNhc2Ugd2FzIGFsbCAzLjE0IGtlcm5lbHMs IHdoaWNoIGlzIGluIHlvdXIgcmFuZ2UgdG9vLgoKPiAgU3RlcHMgdG8gcmVwcm9kdWNlIGFyZSBz aW1wbGU6Cj4gaW50IG1haW4oKSB7Cj4gCXN0cnVjdCB4c19oYW5kbGUgKnhzOwo+IAl4cyA9IHhz X29wZW4oMCk7Cj4gCXhzX3dhdGNoKHhzLCAiZG9taWQiLCAidG9rZW4iKTsKPiAJeHNfcmVhZCh4 cywgMCwgIm5hbWUiLCBOVUxMKTsKPiAJcmV0dXJuIDA7Cj4gfQo+IAo+IHhzX3dhdGNoIGludGVy bmFsbHkgY3JlYXRlcyBuZXcgdGhyZWFkLCB3aGljaCB1c2VzIHJlYWQgdG8gd2FpdCBmb3IgdGhl Cj4gd2F0Y2guIEFuZCBpbiB0aGUgc2FtZSB0aW1lLCB0aGUgcHJvZ3JhbSB0cmllcyB0byByZWFk IHNvbWUgdmFsdWUsCj4gYnV0IGFjdHVhbGx5IGl0IGhhbmdzIGF0IHNlbmRpbmcgdGhlIGNvbW1h bmQgKGJlZm9yZSBldmVuIHNlbmRpbmcgYSBwYXRoIHRvIGJlCj4gcmVhZCkuIFN0cmFjZSBnaXZl cyB0aGlzIChzaW1wbGlmaWVkIGZvciByZWFkYWJpbGl0eSk6Cj4gW3BpZCAgMjQ5NF0gd3JpdGUo MywgIlw0XDBcMFwwXDBcMFwwXDBcMFwwXDBcMFxmXDBcMFwwIiwgMTYwID0gMTYKPiBbcGlkICAy NDk0XSB3cml0ZSgzLCAiZG9taWRcMCIsIDYpICAgICAgPSA2Cj4gW3BpZCAgMjQ5NF0gd3JpdGUo MywgInRva2VuXDAiLCA2KSAgICAgID0gNgo+IFtwaWQgIDI0OTVdIHJlYWQoMywgIDx1bmZpbmlz aGVkIC4uLj4KPiBbcGlkICAyNDk0XSBmdXRleCgweDcxYzBkNCwgRlVURVhfV0FJVF9QUklWQVRF LCAxLCBOVUxMIDx1bmZpbmlzaGVkIC4uLj4KPiBbcGlkICAyNDk1XSA8Li4uIHJlYWQgcmVzdW1l ZD4KPiAiXDE3XDBcMFwwXDM3N1wzNzdcMzc3XDM3N1wyMjB+XDI1NVwyN1xmXDBcMFwwIiwgMTYp ID0gMTYKPiBbcGlkICAyNDk1XSByZWFkKDMsICJkb21pZFwwdG9rZW5cMCIsIDEyKSA9IDEyCj4g W3BpZCAgMjQ5NV0gcmVhZCgzLCAiXDRcMFwwXDBcMFwwXDBcMFwwXDBcMFwwXDNcMFwwXDAiLCAx NikgPSAxNgo+IFtwaWQgIDI0OTVdIHJlYWQoMywgIk9LXDAiLCAzKSAgICAgICAgICA9IDMKPiBb cGlkICAyNDk1XSBmdXRleCgweDcxYzBkNCwgRlVURVhfV0FLRV9PUF9QUklWQVRFLCAxLCAxLCAw eDcxYzBkMCwKPiB7RlVURVhfT1BfU0VULCAwLCBGVVRFWF9PUF9DTVBfR1QsIDF9IDx1bmZpbmlz aGVkIC4uLj4KPiBbcGlkICAyNDk0XSA8Li4uIGZ1dGV4IHJlc3VtZWQ+ICkgICAgICAgPSAwCj4g W3BpZCAgMjQ5NV0gPC4uLiBmdXRleCByZXN1bWVkPiApICAgICAgID0gMQo+IFtwaWQgIDI0OTRd IGZ1dGV4KDB4NzFjMGE4LCBGVVRFWF9XQUlUX1BSSVZBVEUsIDIsIE5VTEwgPHVuZmluaXNoZWQg Li4uPgo+IFtwaWQgIDI0OTVdIGZ1dGV4KDB4NzFjMGE4LCBGVVRFWF9XQUtFX1BSSVZBVEUsIDEg PHVuZmluaXNoZWQgLi4uPgo+IFtwaWQgIDI0OTRdIDwuLi4gZnV0ZXggcmVzdW1lZD4gKSAgICAg ICA9IC0xIEVBR0FJTiAoUmVzb3VyY2UKPiB0ZW1wb3JhcmlseSB1bmF2YWlsYWJsZSkKPiBbcGlk ICAyNDk1XSA8Li4uIGZ1dGV4IHJlc3VtZWQ+ICkgICAgICAgPSAwCj4gW3BpZCAgMjQ5NF0gZnV0 ZXgoMHg3MWMwYTgsIEZVVEVYX1dBS0VfUFJJVkFURSwgMSA8dW5maW5pc2hlZCAuLi4+Cj4gW3Bp ZCAgMjQ5NV0gcmVhZCgzLCAgPHVuZmluaXNoZWQgLi4uPgo+IFtwaWQgIDI0OTRdIDwuLi4gZnV0 ZXggcmVzdW1lZD4gKSAgICAgICA9IDAKPiBbcGlkICAyNDk0XSBydF9zaWdhY3Rpb24oU0lHUElQ RSwge1NJR19ERkwsIFtdLCBTQV9SRVNUT1JFUiwKPiAweDdmYzc4YzE0ODhmMH0sIE5VTEwsIDgp ID0gMAo+IFtwaWQgIDI0OTRdIHJ0X3NpZ2FjdGlvbihTSUdQSVBFLCB7U0lHX0lHTiwgW10sIFNB X1JFU1RPUkVSLAo+IDB4N2ZjNzhjMTQ4OGYwfSwge1NJR19ERkwsIFtdLCBTQV9SRVNUT1JFUiwg MHg3ZmM3OGMxNDg4ZjB9LCA4KSA9IDAKPiBbcGlkICAyNDk0XSB3cml0ZSgzLCAiXDJcMFwwXDBc MFwwXDBcMFwwXDBcMFwwXDVcMFwwXDAiLCAxNgo+IAo+IEFuZCB0aGF0cyBhbGwgLSAyNDk0IGlz IHdhaXRpbmcgb24gd3JpdGUsIDI0OTUgaXMgd2FpdGluZyBvbiByZWFkLgo+IAo+IE9uIDMuMTIu eCBpdCBpcyB3b3JraW5nLiBPbiAzLjE3LjAgYW5kIDMuMTguNyBpdCBpcyBicm9rZW4uIEkgaGF2 ZW4ndAo+IGNoZWNrZWQgdmVyc2lvbnMgaW4gdGhlIG1pZGRsZS4KPiAKPiBBbnkgaWRlYXM/Cj4g Cj4gX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KPiBYZW4t ZGV2ZWwgbWFpbGluZyBsaXN0Cj4gWGVuLWRldmVsQGxpc3RzLnhlbi5vcmcKPiBodHRwOi8vbGlz dHMueGVuLm9yZy94ZW4tZGV2ZWwKCgoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX18KRW1iZWRkZWQtcHYtZGV2ZWwgbWFpbGluZyBsaXN0CkVtYmVkZGVkLXB2 LWRldmVsQGxpc3RzLnhlbnByb2plY3Qub3JnCmh0dHA6Ly9saXN0cy54ZW5wcm9qZWN0Lm9yZy9j Z2ktYmluL21haWxtYW4vbGlzdGluZm8vZW1iZWRkZWQtcHYtZGV2ZWw= From embedded-pv-devel-bounces@lists.xenproject.org Thu Mar 19 10:38:39 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Thu, 19 Mar 2015 10:38:39 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYXqY-0003tQ-Qc; Thu, 19 Mar 2015 10:38:38 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYXqX-0003tC-BB for Embedded-pv-devel@lists.xenproject.org; Thu, 19 Mar 2015 10:38:37 +0000 Received: from [85.158.139.211] by server-8.bemta-5.messagelabs.com id A9/24-16789-C27AA055; Thu, 19 Mar 2015 10:38:36 +0000 X-Env-Sender: Ian.Campbell@citrix.com X-Msg-Ref: server-14.tower-206.messagelabs.com!1426761514!6400748!1 X-Originating-IP: [66.165.176.63] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni42MyA9PiAzMDYwNDg=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 15262 invoked from network); 19 Mar 2015 10:38:36 -0000 Received: from smtp02.citrix.com (HELO SMTP02.CITRIX.COM) (66.165.176.63) by server-14.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 19 Mar 2015 10:38:36 -0000 X-IronPort-AV: E=Sophos;i="5.11,429,1422921600"; d="scan'208";a="246496573" Message-ID: <1426761512.610.18.camel@citrix.com> From: Ian Campbell To: Marek =?ISO-8859-1?Q?Marczykowski-G=F3recki?= Date: Thu, 19 Mar 2015 10:38:32 +0000 In-Reply-To: <20150319011911.GA29029@mail-itl> References: <20150319011911.GA29029@mail-itl> X-Mailer: Evolution 3.12.9-1+b1 MIME-Version: 1.0 X-DLP: MIA1 Cc: Iurii Konovalenko , Embedded-pv-devel@lists.xenproject.org, Boris Ostrovsky , David Vrabel , xen-devel Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org T24gVGh1LCAyMDE1LTAzLTE5IGF0IDAyOjE5ICswMTAwLCBNYXJlayBNYXJjenlrb3dza2ktR8Oz cmVja2kgd3JvdGU6Cj4gSGksCj4gCj4gSSd2ZSBoaXQgc29tZSBkZWFkbG9jayBpbiBrZXJuZWwg eGVuc3RvcmUgY2xpZW50IGV4cG9zZWQgdmlhCj4gL3Byb2MveGVuL3hlbmJ1cy4KClNvdW5kcyBz aW1pbGFyIHRvIHdoYXQgSXVyaWkgYWxzbyByZXBvcnRlZCBsYXN0IG5pZ2h0IGluICJVc2Vyc3Bh Y2UgUFYKYmFja2VuZCBoYW5ncyIuCgpJdXJyaSdzIGNhc2Ugd2FzIGFsbCAzLjE0IGtlcm5lbHMs IHdoaWNoIGlzIGluIHlvdXIgcmFuZ2UgdG9vLgoKPiAgU3RlcHMgdG8gcmVwcm9kdWNlIGFyZSBz aW1wbGU6Cj4gaW50IG1haW4oKSB7Cj4gCXN0cnVjdCB4c19oYW5kbGUgKnhzOwo+IAl4cyA9IHhz X29wZW4oMCk7Cj4gCXhzX3dhdGNoKHhzLCAiZG9taWQiLCAidG9rZW4iKTsKPiAJeHNfcmVhZCh4 cywgMCwgIm5hbWUiLCBOVUxMKTsKPiAJcmV0dXJuIDA7Cj4gfQo+IAo+IHhzX3dhdGNoIGludGVy bmFsbHkgY3JlYXRlcyBuZXcgdGhyZWFkLCB3aGljaCB1c2VzIHJlYWQgdG8gd2FpdCBmb3IgdGhl Cj4gd2F0Y2guIEFuZCBpbiB0aGUgc2FtZSB0aW1lLCB0aGUgcHJvZ3JhbSB0cmllcyB0byByZWFk IHNvbWUgdmFsdWUsCj4gYnV0IGFjdHVhbGx5IGl0IGhhbmdzIGF0IHNlbmRpbmcgdGhlIGNvbW1h bmQgKGJlZm9yZSBldmVuIHNlbmRpbmcgYSBwYXRoIHRvIGJlCj4gcmVhZCkuIFN0cmFjZSBnaXZl cyB0aGlzIChzaW1wbGlmaWVkIGZvciByZWFkYWJpbGl0eSk6Cj4gW3BpZCAgMjQ5NF0gd3JpdGUo MywgIlw0XDBcMFwwXDBcMFwwXDBcMFwwXDBcMFxmXDBcMFwwIiwgMTYwID0gMTYKPiBbcGlkICAy NDk0XSB3cml0ZSgzLCAiZG9taWRcMCIsIDYpICAgICAgPSA2Cj4gW3BpZCAgMjQ5NF0gd3JpdGUo MywgInRva2VuXDAiLCA2KSAgICAgID0gNgo+IFtwaWQgIDI0OTVdIHJlYWQoMywgIDx1bmZpbmlz aGVkIC4uLj4KPiBbcGlkICAyNDk0XSBmdXRleCgweDcxYzBkNCwgRlVURVhfV0FJVF9QUklWQVRF LCAxLCBOVUxMIDx1bmZpbmlzaGVkIC4uLj4KPiBbcGlkICAyNDk1XSA8Li4uIHJlYWQgcmVzdW1l ZD4KPiAiXDE3XDBcMFwwXDM3N1wzNzdcMzc3XDM3N1wyMjB+XDI1NVwyN1xmXDBcMFwwIiwgMTYp ID0gMTYKPiBbcGlkICAyNDk1XSByZWFkKDMsICJkb21pZFwwdG9rZW5cMCIsIDEyKSA9IDEyCj4g W3BpZCAgMjQ5NV0gcmVhZCgzLCAiXDRcMFwwXDBcMFwwXDBcMFwwXDBcMFwwXDNcMFwwXDAiLCAx NikgPSAxNgo+IFtwaWQgIDI0OTVdIHJlYWQoMywgIk9LXDAiLCAzKSAgICAgICAgICA9IDMKPiBb cGlkICAyNDk1XSBmdXRleCgweDcxYzBkNCwgRlVURVhfV0FLRV9PUF9QUklWQVRFLCAxLCAxLCAw eDcxYzBkMCwKPiB7RlVURVhfT1BfU0VULCAwLCBGVVRFWF9PUF9DTVBfR1QsIDF9IDx1bmZpbmlz aGVkIC4uLj4KPiBbcGlkICAyNDk0XSA8Li4uIGZ1dGV4IHJlc3VtZWQ+ICkgICAgICAgPSAwCj4g W3BpZCAgMjQ5NV0gPC4uLiBmdXRleCByZXN1bWVkPiApICAgICAgID0gMQo+IFtwaWQgIDI0OTRd IGZ1dGV4KDB4NzFjMGE4LCBGVVRFWF9XQUlUX1BSSVZBVEUsIDIsIE5VTEwgPHVuZmluaXNoZWQg Li4uPgo+IFtwaWQgIDI0OTVdIGZ1dGV4KDB4NzFjMGE4LCBGVVRFWF9XQUtFX1BSSVZBVEUsIDEg PHVuZmluaXNoZWQgLi4uPgo+IFtwaWQgIDI0OTRdIDwuLi4gZnV0ZXggcmVzdW1lZD4gKSAgICAg ICA9IC0xIEVBR0FJTiAoUmVzb3VyY2UKPiB0ZW1wb3JhcmlseSB1bmF2YWlsYWJsZSkKPiBbcGlk ICAyNDk1XSA8Li4uIGZ1dGV4IHJlc3VtZWQ+ICkgICAgICAgPSAwCj4gW3BpZCAgMjQ5NF0gZnV0 ZXgoMHg3MWMwYTgsIEZVVEVYX1dBS0VfUFJJVkFURSwgMSA8dW5maW5pc2hlZCAuLi4+Cj4gW3Bp ZCAgMjQ5NV0gcmVhZCgzLCAgPHVuZmluaXNoZWQgLi4uPgo+IFtwaWQgIDI0OTRdIDwuLi4gZnV0 ZXggcmVzdW1lZD4gKSAgICAgICA9IDAKPiBbcGlkICAyNDk0XSBydF9zaWdhY3Rpb24oU0lHUElQ RSwge1NJR19ERkwsIFtdLCBTQV9SRVNUT1JFUiwKPiAweDdmYzc4YzE0ODhmMH0sIE5VTEwsIDgp ID0gMAo+IFtwaWQgIDI0OTRdIHJ0X3NpZ2FjdGlvbihTSUdQSVBFLCB7U0lHX0lHTiwgW10sIFNB X1JFU1RPUkVSLAo+IDB4N2ZjNzhjMTQ4OGYwfSwge1NJR19ERkwsIFtdLCBTQV9SRVNUT1JFUiwg MHg3ZmM3OGMxNDg4ZjB9LCA4KSA9IDAKPiBbcGlkICAyNDk0XSB3cml0ZSgzLCAiXDJcMFwwXDBc MFwwXDBcMFwwXDBcMFwwXDVcMFwwXDAiLCAxNgo+IAo+IEFuZCB0aGF0cyBhbGwgLSAyNDk0IGlz IHdhaXRpbmcgb24gd3JpdGUsIDI0OTUgaXMgd2FpdGluZyBvbiByZWFkLgo+IAo+IE9uIDMuMTIu eCBpdCBpcyB3b3JraW5nLiBPbiAzLjE3LjAgYW5kIDMuMTguNyBpdCBpcyBicm9rZW4uIEkgaGF2 ZW4ndAo+IGNoZWNrZWQgdmVyc2lvbnMgaW4gdGhlIG1pZGRsZS4KPiAKPiBBbnkgaWRlYXM/Cj4g Cj4gX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KPiBYZW4t ZGV2ZWwgbWFpbGluZyBsaXN0Cj4gWGVuLWRldmVsQGxpc3RzLnhlbi5vcmcKPiBodHRwOi8vbGlz dHMueGVuLm9yZy94ZW4tZGV2ZWwKCgoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX18KRW1iZWRkZWQtcHYtZGV2ZWwgbWFpbGluZyBsaXN0CkVtYmVkZGVkLXB2 LWRldmVsQGxpc3RzLnhlbnByb2plY3Qub3JnCmh0dHA6Ly9saXN0cy54ZW5wcm9qZWN0Lm9yZy9j Z2ktYmluL21haWxtYW4vbGlzdGluZm8vZW1iZWRkZWQtcHYtZGV2ZWw= From embedded-pv-devel-bounces@lists.xenproject.org Thu Mar 19 12:10:35 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Thu, 19 Mar 2015 12:10:35 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYZHW-000424-T6; Thu, 19 Mar 2015 12:10:34 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYZHV-00040l-Fu for Embedded-pv-devel@lists.xenproject.org; Thu, 19 Mar 2015 12:10:33 +0000 Received: from [193.109.254.147] by server-13.bemta-14.messagelabs.com id 7D/AE-23283-8BCBA055; Thu, 19 Mar 2015 12:10:32 +0000 X-Env-Sender: iurii.konovalenko@globallogic.com X-Msg-Ref: server-11.tower-27.messagelabs.com!1426767029!10934910!1 X-Originating-IP: [64.18.0.20] X-SpamReason: No, hits=0.8 required=7.0 tests=BODY_RANDOM_LONG, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 977 invoked from network); 19 Mar 2015 12:10:30 -0000 Received: from exprod5og110.obsmtp.com (HELO exprod5og110.obsmtp.com) (64.18.0.20) by server-11.tower-27.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 19 Mar 2015 12:10:30 -0000 Received: from mail-ig0-f176.google.com ([209.85.213.176]) (using TLSv1) by exprod5ob110.postini.com ([64.18.4.12]) with SMTP ID DSNKVQq8tDZRdGLBQ7edHG1AMNVWJHxBd/7h@postini.com; Thu, 19 Mar 2015 05:10:30 PDT Received: by igcqo1 with SMTP id qo1so72366822igc.0 for ; Thu, 19 Mar 2015 05:10:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=xgm/k9mZpup4lnQ4bg5EO+KgjL2CEVzm25Q9BpYFUmk=; b=EkU4eDj9sgi7IuFfJUDr8kylkPqDm39U2ZtzR2CzDPGMn+9GcN+0agj9E+wLoGvWcq DUP3WOdpF8bl5ZJ9wzLDpPywX+AEP1ydhT9iF4Id82tPKlwgjPQG/Et/doeSpEGMnJ2f PzjbjY5hLKHAW1vFOTOYViuSsPn9ojhiw77Zc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=xgm/k9mZpup4lnQ4bg5EO+KgjL2CEVzm25Q9BpYFUmk=; b=HiGse4tJ8ywh9wcxdIPrurQSXC9WP692BF5F0HfDIgrOSNteh2+ujKfS38mzvVBSfL 62TutmLX6N9B4dN49ejWH9HCeFmVsY78gOKJvM4KUBaPMuLgvYRQMK0jGfuZF3rpkVem I2GWgoAzOMjXjCRRCWHVuRnpi/8JRR7MNRkor89NeRA9n31C8F0DcufEiaGpFBoTNyXW 3WIqzcJ4/dfffThWv/f72LsRDYDFZOYy1iTpwWgF6I6+UA6bVCfe9ZhnlvIiruCWN2Bv nmu/6qtzUwIogt8wgomNX2jJdvVb5bDgVqSkjTl9Bv5i8e+87ogpMmiAyT+80mzbPpsb fVUA== X-Gm-Message-State: ALoCoQmpudax3oiyzcAOnxnKo53JVmebtIuJJLl6CFiRjyX2v3bqEscmNrYkfCWnIJoHdam5yp4iWX28FAG3rx6Byk8QWzG8rOnOZsnVEtq//gOvnHmqCRq1hTBd92ylfcHCRuWAApWdreQOC34bmb/+97zY/wMu5UaTdDSiu6RRAX67vpAAXmY= X-Received: by 10.50.119.229 with SMTP id kx5mr15489272igb.42.1426767028677; Thu, 19 Mar 2015 05:10:28 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.50.119.229 with SMTP id kx5mr15489229igb.42.1426767028473; Thu, 19 Mar 2015 05:10:28 -0700 (PDT) Received: by 10.36.48.137 with HTTP; Thu, 19 Mar 2015 05:10:28 -0700 (PDT) In-Reply-To: <1426761512.610.18.camel@citrix.com> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> Date: Thu, 19 Mar 2015 14:10:28 +0200 Message-ID: From: Iurii Konovalenko To: Ian Campbell Content-Type: multipart/mixed; boundary=001a11349420e90b940511a31569 Cc: Embedded-pv-devel@lists.xenproject.org, Boris Ostrovsky , David Vrabel , =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= , xen-devel Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --001a11349420e90b940511a31569 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Hi, guys! When I read, that I am not alone and that issue depends on kernel version, I decided to continue investigation. And I found why our threads locks on read/write operations. On Linux kernel 3.14+ syscalls of file read and write changed a bit: fdget() function was replaced by fdget_pos() - it is fdget() function plus additional position mutex lock for files with FMODE_ATOMIC_POS (files for inodes with S_IFREG flag set - regular nodes). As I thought our xen files are not regular and nonseekable, I hoped this flag is not set. But it is set. It is because our file system is created by function simple_fill_super(), and inside it this flag is hardly set: inode->i_mode =3D S_IFREG | files->mode; So, as a fast hack I made a patch: just made copy of this function for xen, which does not set this flag. It works for me. Could you please check if it works for you. Best regards. Iurii Konovalenko | Senior Software Engineer GlobalLogic P +3.8044.492.9695 M +38.099.932.2909 S yufuntik www.globallogic.com http://www.globallogic.com/email_disclaimer.txt On Thu, Mar 19, 2015 at 12:38 PM, Ian Campbell wr= ote: > On Thu, 2015-03-19 at 02:19 +0100, Marek Marczykowski-G=C3=B3recki wrote: >> Hi, >> >> I've hit some deadlock in kernel xenstore client exposed via >> /proc/xen/xenbus. > > Sounds similar to what Iurii also reported last night in "Userspace PV > backend hangs". > > Iurri's case was all 3.14 kernels, which is in your range too. > >> Steps to reproduce are simple: >> int main() { >> struct xs_handle *xs; >> xs =3D xs_open(0); >> xs_watch(xs, "domid", "token"); >> xs_read(xs, 0, "name", NULL); >> return 0; >> } >> >> xs_watch internally creates new thread, which uses read to wait for the >> watch. And in the same time, the program tries to read some value, >> but actually it hangs at sending the command (before even sending a path= to be >> read). Strace gives this (simplified for readability): >> [pid 2494] write(3, "\4\0\0\0\0\0\0\0\0\0\0\0\f\0\0\0", 160 =3D 16 >> [pid 2494] write(3, "domid\0", 6) =3D 6 >> [pid 2494] write(3, "token\0", 6) =3D 6 >> [pid 2495] read(3, >> [pid 2494] futex(0x71c0d4, FUTEX_WAIT_PRIVATE, 1, NULL >> [pid 2495] <... read resumed> >> "\17\0\0\0\377\377\377\377\220~\255\27\f\0\0\0", 16) =3D 16 >> [pid 2495] read(3, "domid\0token\0", 12) =3D 12 >> [pid 2495] read(3, "\4\0\0\0\0\0\0\0\0\0\0\0\3\0\0\0", 16) =3D 16 >> [pid 2495] read(3, "OK\0", 3) =3D 3 >> [pid 2495] futex(0x71c0d4, FUTEX_WAKE_OP_PRIVATE, 1, 1, 0x71c0d0, >> {FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 1} >> [pid 2494] <... futex resumed> ) =3D 0 >> [pid 2495] <... futex resumed> ) =3D 1 >> [pid 2494] futex(0x71c0a8, FUTEX_WAIT_PRIVATE, 2, NULL >> [pid 2495] futex(0x71c0a8, FUTEX_WAKE_PRIVATE, 1 >> [pid 2494] <... futex resumed> ) =3D -1 EAGAIN (Resource >> temporarily unavailable) >> [pid 2495] <... futex resumed> ) =3D 0 >> [pid 2494] futex(0x71c0a8, FUTEX_WAKE_PRIVATE, 1 >> [pid 2495] read(3, >> [pid 2494] <... futex resumed> ) =3D 0 >> [pid 2494] rt_sigaction(SIGPIPE, {SIG_DFL, [], SA_RESTORER, >> 0x7fc78c1488f0}, NULL, 8) =3D 0 >> [pid 2494] rt_sigaction(SIGPIPE, {SIG_IGN, [], SA_RESTORER, >> 0x7fc78c1488f0}, {SIG_DFL, [], SA_RESTORER, 0x7fc78c1488f0}, 8) =3D 0 >> [pid 2494] write(3, "\2\0\0\0\0\0\0\0\0\0\0\0\5\0\0\0", 16 >> >> And thats all - 2494 is waiting on write, 2495 is waiting on read. >> >> On 3.12.x it is working. On 3.17.0 and 3.18.7 it is broken. I haven't >> checked versions in the middle. >> >> Any ideas? >> >> _______________________________________________ >> Xen-devel mailing list >> Xen-devel@lists.xen.org >> http://lists.xen.org/xen-devel > > --001a11349420e90b940511a31569 Content-Type: text/x-patch; charset=US-ASCII; name="0001-arm-xen-hack-to-make-xen-files-unregular.patch" Content-Disposition: attachment; filename="0001-arm-xen-hack-to-make-xen-files-unregular.patch" Content-Transfer-Encoding: base64 X-Attachment-Id: f_i7g487kx0 RnJvbSBlYTU2NDJjMGVhNTM3ZWYzYzlkYTk0NmQ0ZjI2YThmNTk3YjY4NjIyIE1vbiBTZXAgMTcg MDA6MDA6MDAgMjAwMQpGcm9tOiBJdXJpaSBLb25vdmFsZW5rbyA8aXVyaWkua29ub3ZhbGVua29A Z2xvYmFsbG9naWMuY29tPgpEYXRlOiBUaHUsIDE5IE1hciAyMDE1IDEzOjU1OjQ0ICswMjAwClN1 YmplY3Q6IFtQQVRDSF0gYXJtOiB4ZW46IGhhY2sgdG8gbWFrZSB4ZW4gZmlsZXMgdW5yZWd1bGFy CgpDaGFuZ2UtSWQ6IEkwYmMzMjg2N2NhMTJkYWQ3OGFhNWY1MzJhOWM2MDZmYWI5YTNkMWRiClNp Z25lZC1vZmYtYnk6IEl1cmlpIEtvbm92YWxlbmtvIDxpdXJpaS5rb25vdmFsZW5rb0BnbG9iYWxs b2dpYy5jb20+Ci0tLQogZHJpdmVycy94ZW4veGVuZnMvc3VwZXIuYyB8IDcxICsrKysrKysrKysr KysrKysrKysrKysrKysrKysrKysrKysrKysrKysrKysrKystCiAxIGZpbGUgY2hhbmdlZCwgNzAg aW5zZXJ0aW9ucygrKSwgMSBkZWxldGlvbigtKQoKZGlmZiAtLWdpdCBhL2RyaXZlcnMveGVuL3hl bmZzL3N1cGVyLmMgYi9kcml2ZXJzL3hlbi94ZW5mcy9zdXBlci5jCmluZGV4IDA2MDkyZTAuLjFm N2U3NGMgMTAwNjQ0Ci0tLSBhL2RyaXZlcnMveGVuL3hlbmZzL3N1cGVyLmMKKysrIGIvZHJpdmVy cy94ZW4veGVuZnMvc3VwZXIuYwpAQCAtMTQsNiArMTQsNyBAQAogI2luY2x1ZGUgPGxpbnV4L21v ZHVsZS5oPgogI2luY2x1ZGUgPGxpbnV4L2ZzLmg+CiAjaW5jbHVkZSA8bGludXgvbWFnaWMuaD4K KyNpbmNsdWRlIDxsaW51eC9wYWdlbWFwLmg+CiAKICNpbmNsdWRlIDx4ZW4veGVuLmg+CiAKQEAg LTQyLDYgKzQzLDc0IEBAIHN0YXRpYyBjb25zdCBzdHJ1Y3QgZmlsZV9vcGVyYXRpb25zIGNhcGFi aWxpdGllc19maWxlX29wcyA9IHsKIAkubGxzZWVrID0gZGVmYXVsdF9sbHNlZWssCiB9OwogCitz dGF0aWMgY29uc3Qgc3RydWN0IHN1cGVyX29wZXJhdGlvbnMgeGVuX3NpbXBsZV9zdXBlcl9vcGVy YXRpb25zID0geworCS5zdGF0ZnMJCT0gc2ltcGxlX3N0YXRmcywKK307CisKK3N0YXRpYyBpbnQg eGVuX3NpbXBsZV9maWxsX3N1cGVyKHN0cnVjdCBzdXBlcl9ibG9jayAqcywgdW5zaWduZWQgbG9u ZyBtYWdpYywKKwkgICAgICBzdHJ1Y3QgdHJlZV9kZXNjciAqZmlsZXMpCit7CitzdHJ1Y3QgaW5v ZGUgKmlub2RlOworc3RydWN0IGRlbnRyeSAqcm9vdDsKK3N0cnVjdCBkZW50cnkgKmRlbnRyeTsK K2ludCBpOworCitzLT5zX2Jsb2Nrc2l6ZSA9IFBBR0VfQ0FDSEVfU0laRTsKK3MtPnNfYmxvY2tz aXplX2JpdHMgPSBQQUdFX0NBQ0hFX1NISUZUOworcy0+c19tYWdpYyA9IG1hZ2ljOworcy0+c19v cCA9ICZ4ZW5fc2ltcGxlX3N1cGVyX29wZXJhdGlvbnM7CitzLT5zX3RpbWVfZ3JhbiA9IDE7CisK K2lub2RlID0gbmV3X2lub2RlKHMpOworaWYgKCFpbm9kZSkKKwlyZXR1cm4gLUVOT01FTTsKKy8q CisqIGJlY2F1c2UgdGhlIHJvb3QgaW5vZGUgaXMgMSwgdGhlIGZpbGVzIGFycmF5IG11c3Qgbm90 IGNvbnRhaW4gYW4KKyogZW50cnkgYXQgaW5kZXggMQorKi8KK2lub2RlLT5pX2lubyA9IDE7Citp bm9kZS0+aV9tb2RlID0gU19JRkRJUiB8IDA3NTU7Citpbm9kZS0+aV9hdGltZSA9IGlub2RlLT5p X210aW1lID0gaW5vZGUtPmlfY3RpbWUgPSBDVVJSRU5UX1RJTUU7Citpbm9kZS0+aV9vcCA9ICZz aW1wbGVfZGlyX2lub2RlX29wZXJhdGlvbnM7Citpbm9kZS0+aV9mb3AgPSAmc2ltcGxlX2Rpcl9v cGVyYXRpb25zOworc2V0X25saW5rKGlub2RlLCAyKTsKK3Jvb3QgPSBkX21ha2Vfcm9vdChpbm9k ZSk7CitpZiAoIXJvb3QpCisJcmV0dXJuIC1FTk9NRU07Citmb3IgKGkgPSAwOyAhZmlsZXMtPm5h bWUgfHwgZmlsZXMtPm5hbWVbMF07IGkrKywgZmlsZXMrKykgeworCWlmICghZmlsZXMtPm5hbWUp CisJCWNvbnRpbnVlOworCisJLyogd2FybiBpZiBpdCB0cmllcyB0byBjb25mbGljdCB3aXRoIHRo ZSByb290IGlub2RlICovCisJaWYgKHVubGlrZWx5KGkgPT0gMSkpCisJCXByaW50ayhLRVJOX1dB Uk5JTkcgIiVzOiAlcyBwYXNzZWQgaW4gYSBmaWxlcyBhcnJheSIKKwkJCSJ3aXRoIGFuIGluZGV4 IG9mIDEhXG4iLCBfX2Z1bmNfXywKKwkJCXMtPnNfdHlwZS0+bmFtZSk7CisKKwlkZW50cnkgPSBk X2FsbG9jX25hbWUocm9vdCwgZmlsZXMtPm5hbWUpOworCWlmICghZGVudHJ5KQorCQlnb3RvIG91 dDsKKwlpbm9kZSA9IG5ld19pbm9kZShzKTsKKwlpZiAoIWlub2RlKSB7CisJCWRwdXQoZGVudHJ5 KTsKKwkJZ290byBvdXQ7CisJfQorCWlub2RlLT5pX21vZGUgPSBmaWxlcy0+bW9kZTsKKwlpbm9k ZS0+aV9hdGltZSA9IGlub2RlLT5pX210aW1lID0gaW5vZGUtPmlfY3RpbWUgPSBDVVJSRU5UX1RJ TUU7CisJaW5vZGUtPmlfZm9wID0gZmlsZXMtPm9wczsKKwlpbm9kZS0+aV9pbm8gPSBpOworCWRf YWRkKGRlbnRyeSwgaW5vZGUpOworfQorcy0+c19yb290ID0gcm9vdDsKK3JldHVybiAwOworb3V0 OgorZF9nZW5vY2lkZShyb290KTsKK3Nocmlua19kY2FjaGVfcGFyZW50KHJvb3QpOworZHB1dChy b290KTsKK3JldHVybiAtRU5PTUVNOworfQorCisKIHN0YXRpYyBpbnQgeGVuZnNfZmlsbF9zdXBl cihzdHJ1Y3Qgc3VwZXJfYmxvY2sgKnNiLCB2b2lkICpkYXRhLCBpbnQgc2lsZW50KQogewogCXN0 YXRpYyBzdHJ1Y3QgdHJlZV9kZXNjciB4ZW5mc19maWxlc1tdID0gewpAQCAtNjAsNyArMTI5LDcg QEAgc3RhdGljIGludCB4ZW5mc19maWxsX3N1cGVyKHN0cnVjdCBzdXBlcl9ibG9jayAqc2IsIHZv aWQgKmRhdGEsIGludCBzaWxlbnQpCiAJCXsiIn0sCiAJfTsKIAotCXJldHVybiBzaW1wbGVfZmls bF9zdXBlcihzYiwgWEVORlNfU1VQRVJfTUFHSUMsCisJcmV0dXJuIHhlbl9zaW1wbGVfZmlsbF9z dXBlcihzYiwgWEVORlNfU1VQRVJfTUFHSUMsCiAJCQl4ZW5faW5pdGlhbF9kb21haW4oKSA/IHhl bmZzX2luaXRfZmlsZXMgOiB4ZW5mc19maWxlcyk7CiB9CiAKLS0gCjEuOS4xCgo= --001a11349420e90b940511a31569 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --001a11349420e90b940511a31569-- From embedded-pv-devel-bounces@lists.xenproject.org Thu Mar 19 12:10:35 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Thu, 19 Mar 2015 12:10:35 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYZHW-000424-T6; Thu, 19 Mar 2015 12:10:34 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYZHV-00040l-Fu for Embedded-pv-devel@lists.xenproject.org; Thu, 19 Mar 2015 12:10:33 +0000 Received: from [193.109.254.147] by server-13.bemta-14.messagelabs.com id 7D/AE-23283-8BCBA055; Thu, 19 Mar 2015 12:10:32 +0000 X-Env-Sender: iurii.konovalenko@globallogic.com X-Msg-Ref: server-11.tower-27.messagelabs.com!1426767029!10934910!1 X-Originating-IP: [64.18.0.20] X-SpamReason: No, hits=0.8 required=7.0 tests=BODY_RANDOM_LONG, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 977 invoked from network); 19 Mar 2015 12:10:30 -0000 Received: from exprod5og110.obsmtp.com (HELO exprod5og110.obsmtp.com) (64.18.0.20) by server-11.tower-27.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 19 Mar 2015 12:10:30 -0000 Received: from mail-ig0-f176.google.com ([209.85.213.176]) (using TLSv1) by exprod5ob110.postini.com ([64.18.4.12]) with SMTP ID DSNKVQq8tDZRdGLBQ7edHG1AMNVWJHxBd/7h@postini.com; Thu, 19 Mar 2015 05:10:30 PDT Received: by igcqo1 with SMTP id qo1so72366822igc.0 for ; Thu, 19 Mar 2015 05:10:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=xgm/k9mZpup4lnQ4bg5EO+KgjL2CEVzm25Q9BpYFUmk=; b=EkU4eDj9sgi7IuFfJUDr8kylkPqDm39U2ZtzR2CzDPGMn+9GcN+0agj9E+wLoGvWcq DUP3WOdpF8bl5ZJ9wzLDpPywX+AEP1ydhT9iF4Id82tPKlwgjPQG/Et/doeSpEGMnJ2f PzjbjY5hLKHAW1vFOTOYViuSsPn9ojhiw77Zc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=xgm/k9mZpup4lnQ4bg5EO+KgjL2CEVzm25Q9BpYFUmk=; b=HiGse4tJ8ywh9wcxdIPrurQSXC9WP692BF5F0HfDIgrOSNteh2+ujKfS38mzvVBSfL 62TutmLX6N9B4dN49ejWH9HCeFmVsY78gOKJvM4KUBaPMuLgvYRQMK0jGfuZF3rpkVem I2GWgoAzOMjXjCRRCWHVuRnpi/8JRR7MNRkor89NeRA9n31C8F0DcufEiaGpFBoTNyXW 3WIqzcJ4/dfffThWv/f72LsRDYDFZOYy1iTpwWgF6I6+UA6bVCfe9ZhnlvIiruCWN2Bv nmu/6qtzUwIogt8wgomNX2jJdvVb5bDgVqSkjTl9Bv5i8e+87ogpMmiAyT+80mzbPpsb fVUA== X-Gm-Message-State: ALoCoQmpudax3oiyzcAOnxnKo53JVmebtIuJJLl6CFiRjyX2v3bqEscmNrYkfCWnIJoHdam5yp4iWX28FAG3rx6Byk8QWzG8rOnOZsnVEtq//gOvnHmqCRq1hTBd92ylfcHCRuWAApWdreQOC34bmb/+97zY/wMu5UaTdDSiu6RRAX67vpAAXmY= X-Received: by 10.50.119.229 with SMTP id kx5mr15489272igb.42.1426767028677; Thu, 19 Mar 2015 05:10:28 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.50.119.229 with SMTP id kx5mr15489229igb.42.1426767028473; Thu, 19 Mar 2015 05:10:28 -0700 (PDT) Received: by 10.36.48.137 with HTTP; Thu, 19 Mar 2015 05:10:28 -0700 (PDT) In-Reply-To: <1426761512.610.18.camel@citrix.com> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> Date: Thu, 19 Mar 2015 14:10:28 +0200 Message-ID: From: Iurii Konovalenko To: Ian Campbell Content-Type: multipart/mixed; boundary=001a11349420e90b940511a31569 Cc: Embedded-pv-devel@lists.xenproject.org, Boris Ostrovsky , David Vrabel , =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= , xen-devel Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --001a11349420e90b940511a31569 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Hi, guys! When I read, that I am not alone and that issue depends on kernel version, I decided to continue investigation. And I found why our threads locks on read/write operations. On Linux kernel 3.14+ syscalls of file read and write changed a bit: fdget() function was replaced by fdget_pos() - it is fdget() function plus additional position mutex lock for files with FMODE_ATOMIC_POS (files for inodes with S_IFREG flag set - regular nodes). As I thought our xen files are not regular and nonseekable, I hoped this flag is not set. But it is set. It is because our file system is created by function simple_fill_super(), and inside it this flag is hardly set: inode->i_mode =3D S_IFREG | files->mode; So, as a fast hack I made a patch: just made copy of this function for xen, which does not set this flag. It works for me. Could you please check if it works for you. Best regards. Iurii Konovalenko | Senior Software Engineer GlobalLogic P +3.8044.492.9695 M +38.099.932.2909 S yufuntik www.globallogic.com http://www.globallogic.com/email_disclaimer.txt On Thu, Mar 19, 2015 at 12:38 PM, Ian Campbell wr= ote: > On Thu, 2015-03-19 at 02:19 +0100, Marek Marczykowski-G=C3=B3recki wrote: >> Hi, >> >> I've hit some deadlock in kernel xenstore client exposed via >> /proc/xen/xenbus. > > Sounds similar to what Iurii also reported last night in "Userspace PV > backend hangs". > > Iurri's case was all 3.14 kernels, which is in your range too. > >> Steps to reproduce are simple: >> int main() { >> struct xs_handle *xs; >> xs =3D xs_open(0); >> xs_watch(xs, "domid", "token"); >> xs_read(xs, 0, "name", NULL); >> return 0; >> } >> >> xs_watch internally creates new thread, which uses read to wait for the >> watch. And in the same time, the program tries to read some value, >> but actually it hangs at sending the command (before even sending a path= to be >> read). Strace gives this (simplified for readability): >> [pid 2494] write(3, "\4\0\0\0\0\0\0\0\0\0\0\0\f\0\0\0", 160 =3D 16 >> [pid 2494] write(3, "domid\0", 6) =3D 6 >> [pid 2494] write(3, "token\0", 6) =3D 6 >> [pid 2495] read(3, >> [pid 2494] futex(0x71c0d4, FUTEX_WAIT_PRIVATE, 1, NULL >> [pid 2495] <... read resumed> >> "\17\0\0\0\377\377\377\377\220~\255\27\f\0\0\0", 16) =3D 16 >> [pid 2495] read(3, "domid\0token\0", 12) =3D 12 >> [pid 2495] read(3, "\4\0\0\0\0\0\0\0\0\0\0\0\3\0\0\0", 16) =3D 16 >> [pid 2495] read(3, "OK\0", 3) =3D 3 >> [pid 2495] futex(0x71c0d4, FUTEX_WAKE_OP_PRIVATE, 1, 1, 0x71c0d0, >> {FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 1} >> [pid 2494] <... futex resumed> ) =3D 0 >> [pid 2495] <... futex resumed> ) =3D 1 >> [pid 2494] futex(0x71c0a8, FUTEX_WAIT_PRIVATE, 2, NULL >> [pid 2495] futex(0x71c0a8, FUTEX_WAKE_PRIVATE, 1 >> [pid 2494] <... futex resumed> ) =3D -1 EAGAIN (Resource >> temporarily unavailable) >> [pid 2495] <... futex resumed> ) =3D 0 >> [pid 2494] futex(0x71c0a8, FUTEX_WAKE_PRIVATE, 1 >> [pid 2495] read(3, >> [pid 2494] <... futex resumed> ) =3D 0 >> [pid 2494] rt_sigaction(SIGPIPE, {SIG_DFL, [], SA_RESTORER, >> 0x7fc78c1488f0}, NULL, 8) =3D 0 >> [pid 2494] rt_sigaction(SIGPIPE, {SIG_IGN, [], SA_RESTORER, >> 0x7fc78c1488f0}, {SIG_DFL, [], SA_RESTORER, 0x7fc78c1488f0}, 8) =3D 0 >> [pid 2494] write(3, "\2\0\0\0\0\0\0\0\0\0\0\0\5\0\0\0", 16 >> >> And thats all - 2494 is waiting on write, 2495 is waiting on read. >> >> On 3.12.x it is working. On 3.17.0 and 3.18.7 it is broken. I haven't >> checked versions in the middle. >> >> Any ideas? >> >> _______________________________________________ >> Xen-devel mailing list >> Xen-devel@lists.xen.org >> http://lists.xen.org/xen-devel > > --001a11349420e90b940511a31569 Content-Type: text/x-patch; charset=US-ASCII; name="0001-arm-xen-hack-to-make-xen-files-unregular.patch" Content-Disposition: attachment; filename="0001-arm-xen-hack-to-make-xen-files-unregular.patch" Content-Transfer-Encoding: base64 X-Attachment-Id: f_i7g487kx0 RnJvbSBlYTU2NDJjMGVhNTM3ZWYzYzlkYTk0NmQ0ZjI2YThmNTk3YjY4NjIyIE1vbiBTZXAgMTcg MDA6MDA6MDAgMjAwMQpGcm9tOiBJdXJpaSBLb25vdmFsZW5rbyA8aXVyaWkua29ub3ZhbGVua29A Z2xvYmFsbG9naWMuY29tPgpEYXRlOiBUaHUsIDE5IE1hciAyMDE1IDEzOjU1OjQ0ICswMjAwClN1 YmplY3Q6IFtQQVRDSF0gYXJtOiB4ZW46IGhhY2sgdG8gbWFrZSB4ZW4gZmlsZXMgdW5yZWd1bGFy CgpDaGFuZ2UtSWQ6IEkwYmMzMjg2N2NhMTJkYWQ3OGFhNWY1MzJhOWM2MDZmYWI5YTNkMWRiClNp Z25lZC1vZmYtYnk6IEl1cmlpIEtvbm92YWxlbmtvIDxpdXJpaS5rb25vdmFsZW5rb0BnbG9iYWxs b2dpYy5jb20+Ci0tLQogZHJpdmVycy94ZW4veGVuZnMvc3VwZXIuYyB8IDcxICsrKysrKysrKysr KysrKysrKysrKysrKysrKysrKysrKysrKysrKysrKysrKystCiAxIGZpbGUgY2hhbmdlZCwgNzAg aW5zZXJ0aW9ucygrKSwgMSBkZWxldGlvbigtKQoKZGlmZiAtLWdpdCBhL2RyaXZlcnMveGVuL3hl bmZzL3N1cGVyLmMgYi9kcml2ZXJzL3hlbi94ZW5mcy9zdXBlci5jCmluZGV4IDA2MDkyZTAuLjFm N2U3NGMgMTAwNjQ0Ci0tLSBhL2RyaXZlcnMveGVuL3hlbmZzL3N1cGVyLmMKKysrIGIvZHJpdmVy cy94ZW4veGVuZnMvc3VwZXIuYwpAQCAtMTQsNiArMTQsNyBAQAogI2luY2x1ZGUgPGxpbnV4L21v ZHVsZS5oPgogI2luY2x1ZGUgPGxpbnV4L2ZzLmg+CiAjaW5jbHVkZSA8bGludXgvbWFnaWMuaD4K KyNpbmNsdWRlIDxsaW51eC9wYWdlbWFwLmg+CiAKICNpbmNsdWRlIDx4ZW4veGVuLmg+CiAKQEAg LTQyLDYgKzQzLDc0IEBAIHN0YXRpYyBjb25zdCBzdHJ1Y3QgZmlsZV9vcGVyYXRpb25zIGNhcGFi aWxpdGllc19maWxlX29wcyA9IHsKIAkubGxzZWVrID0gZGVmYXVsdF9sbHNlZWssCiB9OwogCitz dGF0aWMgY29uc3Qgc3RydWN0IHN1cGVyX29wZXJhdGlvbnMgeGVuX3NpbXBsZV9zdXBlcl9vcGVy YXRpb25zID0geworCS5zdGF0ZnMJCT0gc2ltcGxlX3N0YXRmcywKK307CisKK3N0YXRpYyBpbnQg eGVuX3NpbXBsZV9maWxsX3N1cGVyKHN0cnVjdCBzdXBlcl9ibG9jayAqcywgdW5zaWduZWQgbG9u ZyBtYWdpYywKKwkgICAgICBzdHJ1Y3QgdHJlZV9kZXNjciAqZmlsZXMpCit7CitzdHJ1Y3QgaW5v ZGUgKmlub2RlOworc3RydWN0IGRlbnRyeSAqcm9vdDsKK3N0cnVjdCBkZW50cnkgKmRlbnRyeTsK K2ludCBpOworCitzLT5zX2Jsb2Nrc2l6ZSA9IFBBR0VfQ0FDSEVfU0laRTsKK3MtPnNfYmxvY2tz aXplX2JpdHMgPSBQQUdFX0NBQ0hFX1NISUZUOworcy0+c19tYWdpYyA9IG1hZ2ljOworcy0+c19v cCA9ICZ4ZW5fc2ltcGxlX3N1cGVyX29wZXJhdGlvbnM7CitzLT5zX3RpbWVfZ3JhbiA9IDE7CisK K2lub2RlID0gbmV3X2lub2RlKHMpOworaWYgKCFpbm9kZSkKKwlyZXR1cm4gLUVOT01FTTsKKy8q CisqIGJlY2F1c2UgdGhlIHJvb3QgaW5vZGUgaXMgMSwgdGhlIGZpbGVzIGFycmF5IG11c3Qgbm90 IGNvbnRhaW4gYW4KKyogZW50cnkgYXQgaW5kZXggMQorKi8KK2lub2RlLT5pX2lubyA9IDE7Citp bm9kZS0+aV9tb2RlID0gU19JRkRJUiB8IDA3NTU7Citpbm9kZS0+aV9hdGltZSA9IGlub2RlLT5p X210aW1lID0gaW5vZGUtPmlfY3RpbWUgPSBDVVJSRU5UX1RJTUU7Citpbm9kZS0+aV9vcCA9ICZz aW1wbGVfZGlyX2lub2RlX29wZXJhdGlvbnM7Citpbm9kZS0+aV9mb3AgPSAmc2ltcGxlX2Rpcl9v cGVyYXRpb25zOworc2V0X25saW5rKGlub2RlLCAyKTsKK3Jvb3QgPSBkX21ha2Vfcm9vdChpbm9k ZSk7CitpZiAoIXJvb3QpCisJcmV0dXJuIC1FTk9NRU07Citmb3IgKGkgPSAwOyAhZmlsZXMtPm5h bWUgfHwgZmlsZXMtPm5hbWVbMF07IGkrKywgZmlsZXMrKykgeworCWlmICghZmlsZXMtPm5hbWUp CisJCWNvbnRpbnVlOworCisJLyogd2FybiBpZiBpdCB0cmllcyB0byBjb25mbGljdCB3aXRoIHRo ZSByb290IGlub2RlICovCisJaWYgKHVubGlrZWx5KGkgPT0gMSkpCisJCXByaW50ayhLRVJOX1dB Uk5JTkcgIiVzOiAlcyBwYXNzZWQgaW4gYSBmaWxlcyBhcnJheSIKKwkJCSJ3aXRoIGFuIGluZGV4 IG9mIDEhXG4iLCBfX2Z1bmNfXywKKwkJCXMtPnNfdHlwZS0+bmFtZSk7CisKKwlkZW50cnkgPSBk X2FsbG9jX25hbWUocm9vdCwgZmlsZXMtPm5hbWUpOworCWlmICghZGVudHJ5KQorCQlnb3RvIG91 dDsKKwlpbm9kZSA9IG5ld19pbm9kZShzKTsKKwlpZiAoIWlub2RlKSB7CisJCWRwdXQoZGVudHJ5 KTsKKwkJZ290byBvdXQ7CisJfQorCWlub2RlLT5pX21vZGUgPSBmaWxlcy0+bW9kZTsKKwlpbm9k ZS0+aV9hdGltZSA9IGlub2RlLT5pX210aW1lID0gaW5vZGUtPmlfY3RpbWUgPSBDVVJSRU5UX1RJ TUU7CisJaW5vZGUtPmlfZm9wID0gZmlsZXMtPm9wczsKKwlpbm9kZS0+aV9pbm8gPSBpOworCWRf YWRkKGRlbnRyeSwgaW5vZGUpOworfQorcy0+c19yb290ID0gcm9vdDsKK3JldHVybiAwOworb3V0 OgorZF9nZW5vY2lkZShyb290KTsKK3Nocmlua19kY2FjaGVfcGFyZW50KHJvb3QpOworZHB1dChy b290KTsKK3JldHVybiAtRU5PTUVNOworfQorCisKIHN0YXRpYyBpbnQgeGVuZnNfZmlsbF9zdXBl cihzdHJ1Y3Qgc3VwZXJfYmxvY2sgKnNiLCB2b2lkICpkYXRhLCBpbnQgc2lsZW50KQogewogCXN0 YXRpYyBzdHJ1Y3QgdHJlZV9kZXNjciB4ZW5mc19maWxlc1tdID0gewpAQCAtNjAsNyArMTI5LDcg QEAgc3RhdGljIGludCB4ZW5mc19maWxsX3N1cGVyKHN0cnVjdCBzdXBlcl9ibG9jayAqc2IsIHZv aWQgKmRhdGEsIGludCBzaWxlbnQpCiAJCXsiIn0sCiAJfTsKIAotCXJldHVybiBzaW1wbGVfZmls bF9zdXBlcihzYiwgWEVORlNfU1VQRVJfTUFHSUMsCisJcmV0dXJuIHhlbl9zaW1wbGVfZmlsbF9z dXBlcihzYiwgWEVORlNfU1VQRVJfTUFHSUMsCiAJCQl4ZW5faW5pdGlhbF9kb21haW4oKSA/IHhl bmZzX2luaXRfZmlsZXMgOiB4ZW5mc19maWxlcyk7CiB9CiAKLS0gCjEuOS4xCgo= --001a11349420e90b940511a31569 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --001a11349420e90b940511a31569-- From embedded-pv-devel-bounces@lists.xenproject.org Thu Mar 19 12:32:59 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Thu, 19 Mar 2015 12:32:59 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYZdD-0007LQ-N0; Thu, 19 Mar 2015 12:32:59 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYZdC-0007L6-6V for Embedded-pv-devel@lists.xenproject.org; Thu, 19 Mar 2015 12:32:58 +0000 Received: from [85.158.137.68] by server-13.bemta-3.messagelabs.com id 9C/9D-17064-9F1CA055; Thu, 19 Mar 2015 12:32:57 +0000 X-Env-Sender: vitalii.chernookyi@globallogic.com X-Msg-Ref: server-9.tower-31.messagelabs.com!1426768372!9946223!1 X-Originating-IP: [64.18.0.188] X-SpamReason: No, hits=0.4 required=7.0 tests=HTML_30_40,HTML_MESSAGE, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 17084 invoked from network); 19 Mar 2015 12:32:54 -0000 Received: from exprod5og109.obsmtp.com (HELO exprod5og109.obsmtp.com) (64.18.0.188) by server-9.tower-31.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 19 Mar 2015 12:32:54 -0000 Received: from mail-qc0-f170.google.com ([209.85.216.170]) (using TLSv1) by exprod5ob109.postini.com ([64.18.4.12]) with SMTP ID DSNKVQrB9MZxB7XX0dz2DBZWmGRNkDJ39LV3@postini.com; Thu, 19 Mar 2015 05:32:54 PDT Received: by qcbkw5 with SMTP id kw5so64229435qcb.2 for ; Thu, 19 Mar 2015 05:32:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=o4LtSWyQhwC0cs/8tdvgPALP4z6JmHXJPuL7ABcDBSY=; b=Y0kA8e+ZNjIgZLUGbzS0yVW5ENPNOZZl2Sd0GXV95sBNDFyqjk282B+nEwahlklPqN BTYw1hUVz25xxmK0UYa/XuyTJ4kVsO/YN3urToc2jamioGfadg9YrA32wQxuovJH/Z64 KjJQOcW19WC63BCoK37bDQG9qq00pHgkuEYTQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=o4LtSWyQhwC0cs/8tdvgPALP4z6JmHXJPuL7ABcDBSY=; b=bW5RDvfwLlZE9EQelQvnI9diRMSoVnZnEK3AJkgX/zMCyhNszOqUDPRK/3WnNtEeOg RZyAST0IPNRjbicI81rzl9bySUjFw2YBMcYhERrsC/8A8OEG06JDOOGWir5pjJ5/WgAF nPuVPB+PDa4Cc74biFAGqOCCTdu0q9F23vuzTxSYc3sDsjWROB2B1tRY/G2TNlvoZKB+ VitiDsUOzDKcK16bZCSyicefH+K0zIYjmSvKARWJOgpULvHzLzjVnCAfzwOFcv1MBaQf G2Ka+Ip0HQ1Ms8SHu86rhw1A0+7JIAPyNvGRssAX7ATT8TH4bLZ/PVAQtviUvrrw3B8A 489Q== X-Gm-Message-State: ALoCoQm5Qqeu3MhYmbiANkbyjfWUCbLm7yS1DPvXLhu95ZmgeUOw+cMYdzXEJHhrWapYsHl3SgjdpjqJ1sg/dTFPapZFE0PGyXXF+SjXIRbxHvD1C5qEp1bvZOSAwgZO0P1U28LBHFhvCYnt+iifmoXfjdddl9ljq757j84k+UsudnJL3obEPWQ= X-Received: by 10.140.145.203 with SMTP id 194mr98078286qhr.102.1426768371714; Thu, 19 Mar 2015 05:32:51 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.140.145.203 with SMTP id 194mr98078268qhr.102.1426768371558; Thu, 19 Mar 2015 05:32:51 -0700 (PDT) Received: by 10.140.98.145 with HTTP; Thu, 19 Mar 2015 05:32:51 -0700 (PDT) In-Reply-To: References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> Date: Thu, 19 Mar 2015 14:32:51 +0200 Message-ID: From: Vitaly Chernooky To: Iurii Konovalenko Cc: Ian Campbell , =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= , xen-devel , Embedded-pv-devel@lists.xenproject.org, David Vrabel , Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============2416449970709874428==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============2416449970709874428== Content-Type: multipart/alternative; boundary=001a11354880f6c28b0511a365f7 --001a11354880f6c28b0511a365f7 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Hi All! This issue is discussed in details here: https://lkml.org/lkml/2014/2/17/32= 4 With best regards, On Thu, Mar 19, 2015 at 2:10 PM, Iurii Konovalenko < iurii.konovalenko@globallogic.com> wrote: > Hi, guys! > > When I read, that I am not alone and that issue depends on kernel > version, I decided to continue investigation. > And I found why our threads locks on read/write operations. > On Linux kernel 3.14+ syscalls of file read and write changed a bit: > fdget() function was replaced by fdget_pos() - it is fdget() function > plus additional position mutex lock for files with FMODE_ATOMIC_POS > (files for inodes with S_IFREG flag set - regular nodes). As I thought > our xen files are not regular and nonseekable, I hoped this flag is > not set. But it is set. It is because our file system is created by > function simple_fill_super(), and inside it this flag is hardly set: > inode->i_mode =3D S_IFREG | files->mode; > So, as a fast hack I made a patch: just made copy of this function for > xen, which does not set this flag. It works for me. Could you please > check if it works for you. > Best regards. > > Iurii Konovalenko | Senior Software Engineer > GlobalLogic > P +3.8044.492.9695 M +38.099.932.2909 > S yufuntik > www.globallogic.com > http://www.globallogic.com/email_disclaimer.txt > > > On Thu, Mar 19, 2015 at 12:38 PM, Ian Campbell > wrote: > > On Thu, 2015-03-19 at 02:19 +0100, Marek Marczykowski-G=C3=B3recki wrot= e: > >> Hi, > >> > >> I've hit some deadlock in kernel xenstore client exposed via > >> /proc/xen/xenbus. > > > > Sounds similar to what Iurii also reported last night in "Userspace PV > > backend hangs". > > > > Iurri's case was all 3.14 kernels, which is in your range too. > > > >> Steps to reproduce are simple: > >> int main() { > >> struct xs_handle *xs; > >> xs =3D xs_open(0); > >> xs_watch(xs, "domid", "token"); > >> xs_read(xs, 0, "name", NULL); > >> return 0; > >> } > >> > >> xs_watch internally creates new thread, which uses read to wait for th= e > >> watch. And in the same time, the program tries to read some value, > >> but actually it hangs at sending the command (before even sending a > path to be > >> read). Strace gives this (simplified for readability): > >> [pid 2494] write(3, "\4\0\0\0\0\0\0\0\0\0\0\0\f\0\0\0", 160 =3D 16 > >> [pid 2494] write(3, "domid\0", 6) =3D 6 > >> [pid 2494] write(3, "token\0", 6) =3D 6 > >> [pid 2495] read(3, > >> [pid 2494] futex(0x71c0d4, FUTEX_WAIT_PRIVATE, 1, NULL > >> [pid 2495] <... read resumed> > >> "\17\0\0\0\377\377\377\377\220~\255\27\f\0\0\0", 16) =3D 16 > >> [pid 2495] read(3, "domid\0token\0", 12) =3D 12 > >> [pid 2495] read(3, "\4\0\0\0\0\0\0\0\0\0\0\0\3\0\0\0", 16) =3D 16 > >> [pid 2495] read(3, "OK\0", 3) =3D 3 > >> [pid 2495] futex(0x71c0d4, FUTEX_WAKE_OP_PRIVATE, 1, 1, 0x71c0d0, > >> {FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 1} > >> [pid 2494] <... futex resumed> ) =3D 0 > >> [pid 2495] <... futex resumed> ) =3D 1 > >> [pid 2494] futex(0x71c0a8, FUTEX_WAIT_PRIVATE, 2, NULL > >> [pid 2495] futex(0x71c0a8, FUTEX_WAKE_PRIVATE, 1 > >> [pid 2494] <... futex resumed> ) =3D -1 EAGAIN (Resource > >> temporarily unavailable) > >> [pid 2495] <... futex resumed> ) =3D 0 > >> [pid 2494] futex(0x71c0a8, FUTEX_WAKE_PRIVATE, 1 > >> [pid 2495] read(3, > >> [pid 2494] <... futex resumed> ) =3D 0 > >> [pid 2494] rt_sigaction(SIGPIPE, {SIG_DFL, [], SA_RESTORER, > >> 0x7fc78c1488f0}, NULL, 8) =3D 0 > >> [pid 2494] rt_sigaction(SIGPIPE, {SIG_IGN, [], SA_RESTORER, > >> 0x7fc78c1488f0}, {SIG_DFL, [], SA_RESTORER, 0x7fc78c1488f0}, 8) =3D 0 > >> [pid 2494] write(3, "\2\0\0\0\0\0\0\0\0\0\0\0\5\0\0\0", 16 > >> > >> And thats all - 2494 is waiting on write, 2495 is waiting on read. > >> > >> On 3.12.x it is working. On 3.17.0 and 3.18.7 it is broken. I haven't > >> checked versions in the middle. > >> > >> Any ideas? > >> > >> _______________________________________________ > >> Xen-devel mailing list > >> Xen-devel@lists.xen.org > >> http://lists.xen.org/xen-devel > > > > > > _______________________________________________ > Embedded-pv-devel mailing list > Embedded-pv-devel@lists.xenproject.org > http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel > --=20 *Vitaly Chernooky | Senior Developer - Product Engineering and Development* GlobalLogic P *+380.44.4929695 ext.1136* M *+380.63.6011802* S cvv_2k www.globallogic.com http://www.globallogic.com/email_disclaimer.txt --001a11354880f6c28b0511a365f7 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Hi All!

This issue is discussed i= n details here:=C2=A0https:= //lkml.org/lkml/2014/2/17/324

With best regards,

On Thu, M= ar 19, 2015 at 2:10 PM, Iurii Konovalenko <iurii.konovalen= ko@globallogic.com> wrote:
= Hi, guys!

When I read, that I am not alone and that issue depends on kernel
version, I decided to continue investigation.
And I found why our threads locks on read/write operations.
On Linux kernel 3.14+ syscalls of file read and write changed a bit:
fdget() function was replaced by fdget_pos() - it is fdget() function
plus additional position mutex lock for files with FMODE_ATOMIC_POS
(files for inodes with S_IFREG flag set - regular nodes). As I thought
our xen files are not regular and nonseekable, I hoped this flag is
not set. But it is set. It is because our file system is created by
function simple_fill_super(), and inside it this flag is hardly set:
inode->i_mode =3D S_IFREG | files->mode;
So, as a fast hack I made a patch: just made copy of this function for
xen, which does not set this flag. It works for me. Could you please
check if it works for you.
Best regards.

Iurii Konovalenko | Senior Software Engineer
GlobalLogic
P +3.8044.492.96= 95 M +38.099= .932.2909
S yufuntik
www.globallogic.co= m
http://www.globallogic.com/email_disclaimer.txt


On Thu, Mar 19, 2015 at 12:38 PM, Ian Campbell <ian.campbell@citrix.com> wrote:
> On Thu, 2015-03-19 at 02:19 +0100, Marek Marczykowski-G=C3=B3recki wro= te:
>> Hi,
>>
>> I've hit some deadlock in kernel xenstore client exposed via >> /proc/xen/xenbus.
>
> Sounds similar to what Iurii also reported last night in "Userspa= ce PV
> backend hangs".
>
> Iurri's case was all 3.14 kernels, which is in your range too.
>
>>=C2=A0 Steps to reproduce are simple:
>> int main() {
>>=C2=A0 =C2=A0 =C2=A0 =C2=A0struct xs_handle *xs;
>>=C2=A0 =C2=A0 =C2=A0 =C2=A0xs =3D xs_open(0);
>>=C2=A0 =C2=A0 =C2=A0 =C2=A0xs_watch(xs, "domid", "to= ken");
>>=C2=A0 =C2=A0 =C2=A0 =C2=A0xs_read(xs, 0, "name", NULL);<= br> >>=C2=A0 =C2=A0 =C2=A0 =C2=A0return 0;
>> }
>>
>> xs_watch internally creates new thread, which uses read to wait fo= r the
>> watch. And in the same time, the program tries to read some value,=
>> but actually it hangs at sending the command (before even sending = a path to be
>> read). Strace gives this (simplified for readability):
>> [pid=C2=A0 2494] write(3, "\4\0\0\0\0\0\0\0\0\0\0\0\f\0\0\0&q= uot;, 160 =3D 16
>> [pid=C2=A0 2494] write(3, "domid\0", 6)=C2=A0 =C2=A0 =C2= =A0 =3D 6
>> [pid=C2=A0 2494] write(3, "token\0", 6)=C2=A0 =C2=A0 =C2= =A0 =3D 6
>> [pid=C2=A0 2495] read(3,=C2=A0 <unfinished ...>
>> [pid=C2=A0 2494] futex(0x71c0d4, FUTEX_WAIT_PRIVATE, 1, NULL <u= nfinished ...>
>> [pid=C2=A0 2495] <... read resumed>
>> "\17\0\0\0\377\377\377\377\220~\255\27\f\0\0\0", 16) =3D= 16
>> [pid=C2=A0 2495] read(3, "domid\0token\0", 12) =3D 12 >> [pid=C2=A0 2495] read(3, "\4\0\0\0\0\0\0\0\0\0\0\0\3\0\0\0&qu= ot;, 16) =3D 16
>> [pid=C2=A0 2495] read(3, "OK\0", 3)=C2=A0 =C2=A0 =C2=A0 = =C2=A0 =C2=A0 =3D 3
>> [pid=C2=A0 2495] futex(0x71c0d4, FUTEX_WAKE_OP_PRIVATE, 1, 1, 0x71= c0d0,
>> {FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 1} <unfinished ...>
>> [pid=C2=A0 2494] <... futex resumed> )=C2=A0 =C2=A0 =C2=A0 = =C2=A0=3D 0
>> [pid=C2=A0 2495] <... futex resumed> )=C2=A0 =C2=A0 =C2=A0 = =C2=A0=3D 1
>> [pid=C2=A0 2494] futex(0x71c0a8, FUTEX_WAIT_PRIVATE, 2, NULL <u= nfinished ...>
>> [pid=C2=A0 2495] futex(0x71c0a8, FUTEX_WAKE_PRIVATE, 1 <unfinis= hed ...>
>> [pid=C2=A0 2494] <... futex resumed> )=C2=A0 =C2=A0 =C2=A0 = =C2=A0=3D -1 EAGAIN (Resource
>> temporarily unavailable)
>> [pid=C2=A0 2495] <... futex resumed> )=C2=A0 =C2=A0 =C2=A0 = =C2=A0=3D 0
>> [pid=C2=A0 2494] futex(0x71c0a8, FUTEX_WAKE_PRIVATE, 1 <unfinis= hed ...>
>> [pid=C2=A0 2495] read(3,=C2=A0 <unfinished ...>
>> [pid=C2=A0 2494] <... futex resumed> )=C2=A0 =C2=A0 =C2=A0 = =C2=A0=3D 0
>> [pid=C2=A0 2494] rt_sigaction(SIGPIPE, {SIG_DFL, [], SA_RESTORER,<= br> >> 0x7fc78c1488f0}, NULL, 8) =3D 0
>> [pid=C2=A0 2494] rt_sigaction(SIGPIPE, {SIG_IGN, [], SA_RESTORER,<= br> >> 0x7fc78c1488f0}, {SIG_DFL, [], SA_RESTORER, 0x7fc78c1488f0}, 8) = =3D 0
>> [pid=C2=A0 2494] write(3, "\2\0\0\0\0\0\0\0\0\0\0\0\5\0\0\0&q= uot;, 16
>>
>> And thats all - 2494 is waiting on write, 2495 is waiting on read.=
>>
>> On 3.12.x it is working. On 3.17.0 and 3.18.7 it is broken. I have= n't
>> checked versions in the middle.
>>
>> Any ideas?
>>
>> _______________________________________________
>> Xen-devel mailing list
>> Xen-devel@lists.xen.org=
>> http:= //lists.xen.org/xen-devel
>
>

_______________________________________________
Embedded-pv-devel mailing list
Embedded-pv-devel= @lists.xenproject.org
http://lists.xenproject.org/cgi-bin/mailman/listi= nfo/embedded-pv-devel


=
--
Vitaly Chernooky |=C2=A0Senior = Developer - Product Engineering and Development
Global= Logic
P +380.44.4929695 ext.1136 M +380.63.6011802=C2=A0S cvv_2k
<= div>
--001a11354880f6c28b0511a365f7-- --===============2416449970709874428== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============2416449970709874428==-- From embedded-pv-devel-bounces@lists.xenproject.org Thu Mar 19 12:32:59 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Thu, 19 Mar 2015 12:32:59 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYZdD-0007LQ-N0; Thu, 19 Mar 2015 12:32:59 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYZdC-0007L6-6V for Embedded-pv-devel@lists.xenproject.org; Thu, 19 Mar 2015 12:32:58 +0000 Received: from [85.158.137.68] by server-13.bemta-3.messagelabs.com id 9C/9D-17064-9F1CA055; Thu, 19 Mar 2015 12:32:57 +0000 X-Env-Sender: vitalii.chernookyi@globallogic.com X-Msg-Ref: server-9.tower-31.messagelabs.com!1426768372!9946223!1 X-Originating-IP: [64.18.0.188] X-SpamReason: No, hits=0.4 required=7.0 tests=HTML_30_40,HTML_MESSAGE, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 17084 invoked from network); 19 Mar 2015 12:32:54 -0000 Received: from exprod5og109.obsmtp.com (HELO exprod5og109.obsmtp.com) (64.18.0.188) by server-9.tower-31.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 19 Mar 2015 12:32:54 -0000 Received: from mail-qc0-f170.google.com ([209.85.216.170]) (using TLSv1) by exprod5ob109.postini.com ([64.18.4.12]) with SMTP ID DSNKVQrB9MZxB7XX0dz2DBZWmGRNkDJ39LV3@postini.com; Thu, 19 Mar 2015 05:32:54 PDT Received: by qcbkw5 with SMTP id kw5so64229435qcb.2 for ; Thu, 19 Mar 2015 05:32:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=o4LtSWyQhwC0cs/8tdvgPALP4z6JmHXJPuL7ABcDBSY=; b=Y0kA8e+ZNjIgZLUGbzS0yVW5ENPNOZZl2Sd0GXV95sBNDFyqjk282B+nEwahlklPqN BTYw1hUVz25xxmK0UYa/XuyTJ4kVsO/YN3urToc2jamioGfadg9YrA32wQxuovJH/Z64 KjJQOcW19WC63BCoK37bDQG9qq00pHgkuEYTQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=o4LtSWyQhwC0cs/8tdvgPALP4z6JmHXJPuL7ABcDBSY=; b=bW5RDvfwLlZE9EQelQvnI9diRMSoVnZnEK3AJkgX/zMCyhNszOqUDPRK/3WnNtEeOg RZyAST0IPNRjbicI81rzl9bySUjFw2YBMcYhERrsC/8A8OEG06JDOOGWir5pjJ5/WgAF nPuVPB+PDa4Cc74biFAGqOCCTdu0q9F23vuzTxSYc3sDsjWROB2B1tRY/G2TNlvoZKB+ VitiDsUOzDKcK16bZCSyicefH+K0zIYjmSvKARWJOgpULvHzLzjVnCAfzwOFcv1MBaQf G2Ka+Ip0HQ1Ms8SHu86rhw1A0+7JIAPyNvGRssAX7ATT8TH4bLZ/PVAQtviUvrrw3B8A 489Q== X-Gm-Message-State: ALoCoQm5Qqeu3MhYmbiANkbyjfWUCbLm7yS1DPvXLhu95ZmgeUOw+cMYdzXEJHhrWapYsHl3SgjdpjqJ1sg/dTFPapZFE0PGyXXF+SjXIRbxHvD1C5qEp1bvZOSAwgZO0P1U28LBHFhvCYnt+iifmoXfjdddl9ljq757j84k+UsudnJL3obEPWQ= X-Received: by 10.140.145.203 with SMTP id 194mr98078286qhr.102.1426768371714; Thu, 19 Mar 2015 05:32:51 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.140.145.203 with SMTP id 194mr98078268qhr.102.1426768371558; Thu, 19 Mar 2015 05:32:51 -0700 (PDT) Received: by 10.140.98.145 with HTTP; Thu, 19 Mar 2015 05:32:51 -0700 (PDT) In-Reply-To: References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> Date: Thu, 19 Mar 2015 14:32:51 +0200 Message-ID: From: Vitaly Chernooky To: Iurii Konovalenko Cc: Ian Campbell , =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= , xen-devel , Embedded-pv-devel@lists.xenproject.org, David Vrabel , Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============2416449970709874428==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============2416449970709874428== Content-Type: multipart/alternative; boundary=001a11354880f6c28b0511a365f7 --001a11354880f6c28b0511a365f7 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Hi All! This issue is discussed in details here: https://lkml.org/lkml/2014/2/17/32= 4 With best regards, On Thu, Mar 19, 2015 at 2:10 PM, Iurii Konovalenko < iurii.konovalenko@globallogic.com> wrote: > Hi, guys! > > When I read, that I am not alone and that issue depends on kernel > version, I decided to continue investigation. > And I found why our threads locks on read/write operations. > On Linux kernel 3.14+ syscalls of file read and write changed a bit: > fdget() function was replaced by fdget_pos() - it is fdget() function > plus additional position mutex lock for files with FMODE_ATOMIC_POS > (files for inodes with S_IFREG flag set - regular nodes). As I thought > our xen files are not regular and nonseekable, I hoped this flag is > not set. But it is set. It is because our file system is created by > function simple_fill_super(), and inside it this flag is hardly set: > inode->i_mode =3D S_IFREG | files->mode; > So, as a fast hack I made a patch: just made copy of this function for > xen, which does not set this flag. It works for me. Could you please > check if it works for you. > Best regards. > > Iurii Konovalenko | Senior Software Engineer > GlobalLogic > P +3.8044.492.9695 M +38.099.932.2909 > S yufuntik > www.globallogic.com > http://www.globallogic.com/email_disclaimer.txt > > > On Thu, Mar 19, 2015 at 12:38 PM, Ian Campbell > wrote: > > On Thu, 2015-03-19 at 02:19 +0100, Marek Marczykowski-G=C3=B3recki wrot= e: > >> Hi, > >> > >> I've hit some deadlock in kernel xenstore client exposed via > >> /proc/xen/xenbus. > > > > Sounds similar to what Iurii also reported last night in "Userspace PV > > backend hangs". > > > > Iurri's case was all 3.14 kernels, which is in your range too. > > > >> Steps to reproduce are simple: > >> int main() { > >> struct xs_handle *xs; > >> xs =3D xs_open(0); > >> xs_watch(xs, "domid", "token"); > >> xs_read(xs, 0, "name", NULL); > >> return 0; > >> } > >> > >> xs_watch internally creates new thread, which uses read to wait for th= e > >> watch. And in the same time, the program tries to read some value, > >> but actually it hangs at sending the command (before even sending a > path to be > >> read). Strace gives this (simplified for readability): > >> [pid 2494] write(3, "\4\0\0\0\0\0\0\0\0\0\0\0\f\0\0\0", 160 =3D 16 > >> [pid 2494] write(3, "domid\0", 6) =3D 6 > >> [pid 2494] write(3, "token\0", 6) =3D 6 > >> [pid 2495] read(3, > >> [pid 2494] futex(0x71c0d4, FUTEX_WAIT_PRIVATE, 1, NULL > >> [pid 2495] <... read resumed> > >> "\17\0\0\0\377\377\377\377\220~\255\27\f\0\0\0", 16) =3D 16 > >> [pid 2495] read(3, "domid\0token\0", 12) =3D 12 > >> [pid 2495] read(3, "\4\0\0\0\0\0\0\0\0\0\0\0\3\0\0\0", 16) =3D 16 > >> [pid 2495] read(3, "OK\0", 3) =3D 3 > >> [pid 2495] futex(0x71c0d4, FUTEX_WAKE_OP_PRIVATE, 1, 1, 0x71c0d0, > >> {FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 1} > >> [pid 2494] <... futex resumed> ) =3D 0 > >> [pid 2495] <... futex resumed> ) =3D 1 > >> [pid 2494] futex(0x71c0a8, FUTEX_WAIT_PRIVATE, 2, NULL > >> [pid 2495] futex(0x71c0a8, FUTEX_WAKE_PRIVATE, 1 > >> [pid 2494] <... futex resumed> ) =3D -1 EAGAIN (Resource > >> temporarily unavailable) > >> [pid 2495] <... futex resumed> ) =3D 0 > >> [pid 2494] futex(0x71c0a8, FUTEX_WAKE_PRIVATE, 1 > >> [pid 2495] read(3, > >> [pid 2494] <... futex resumed> ) =3D 0 > >> [pid 2494] rt_sigaction(SIGPIPE, {SIG_DFL, [], SA_RESTORER, > >> 0x7fc78c1488f0}, NULL, 8) =3D 0 > >> [pid 2494] rt_sigaction(SIGPIPE, {SIG_IGN, [], SA_RESTORER, > >> 0x7fc78c1488f0}, {SIG_DFL, [], SA_RESTORER, 0x7fc78c1488f0}, 8) =3D 0 > >> [pid 2494] write(3, "\2\0\0\0\0\0\0\0\0\0\0\0\5\0\0\0", 16 > >> > >> And thats all - 2494 is waiting on write, 2495 is waiting on read. > >> > >> On 3.12.x it is working. On 3.17.0 and 3.18.7 it is broken. I haven't > >> checked versions in the middle. > >> > >> Any ideas? > >> > >> _______________________________________________ > >> Xen-devel mailing list > >> Xen-devel@lists.xen.org > >> http://lists.xen.org/xen-devel > > > > > > _______________________________________________ > Embedded-pv-devel mailing list > Embedded-pv-devel@lists.xenproject.org > http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel > --=20 *Vitaly Chernooky | Senior Developer - Product Engineering and Development* GlobalLogic P *+380.44.4929695 ext.1136* M *+380.63.6011802* S cvv_2k www.globallogic.com http://www.globallogic.com/email_disclaimer.txt --001a11354880f6c28b0511a365f7 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Hi All!

This issue is discussed i= n details here:=C2=A0https:= //lkml.org/lkml/2014/2/17/324

With best regards,

On Thu, M= ar 19, 2015 at 2:10 PM, Iurii Konovalenko <iurii.konovalen= ko@globallogic.com> wrote:
= Hi, guys!

When I read, that I am not alone and that issue depends on kernel
version, I decided to continue investigation.
And I found why our threads locks on read/write operations.
On Linux kernel 3.14+ syscalls of file read and write changed a bit:
fdget() function was replaced by fdget_pos() - it is fdget() function
plus additional position mutex lock for files with FMODE_ATOMIC_POS
(files for inodes with S_IFREG flag set - regular nodes). As I thought
our xen files are not regular and nonseekable, I hoped this flag is
not set. But it is set. It is because our file system is created by
function simple_fill_super(), and inside it this flag is hardly set:
inode->i_mode =3D S_IFREG | files->mode;
So, as a fast hack I made a patch: just made copy of this function for
xen, which does not set this flag. It works for me. Could you please
check if it works for you.
Best regards.

Iurii Konovalenko | Senior Software Engineer
GlobalLogic
P +3.8044.492.96= 95 M +38.099= .932.2909
S yufuntik
www.globallogic.co= m
http://www.globallogic.com/email_disclaimer.txt


On Thu, Mar 19, 2015 at 12:38 PM, Ian Campbell <ian.campbell@citrix.com> wrote:
> On Thu, 2015-03-19 at 02:19 +0100, Marek Marczykowski-G=C3=B3recki wro= te:
>> Hi,
>>
>> I've hit some deadlock in kernel xenstore client exposed via >> /proc/xen/xenbus.
>
> Sounds similar to what Iurii also reported last night in "Userspa= ce PV
> backend hangs".
>
> Iurri's case was all 3.14 kernels, which is in your range too.
>
>>=C2=A0 Steps to reproduce are simple:
>> int main() {
>>=C2=A0 =C2=A0 =C2=A0 =C2=A0struct xs_handle *xs;
>>=C2=A0 =C2=A0 =C2=A0 =C2=A0xs =3D xs_open(0);
>>=C2=A0 =C2=A0 =C2=A0 =C2=A0xs_watch(xs, "domid", "to= ken");
>>=C2=A0 =C2=A0 =C2=A0 =C2=A0xs_read(xs, 0, "name", NULL);<= br> >>=C2=A0 =C2=A0 =C2=A0 =C2=A0return 0;
>> }
>>
>> xs_watch internally creates new thread, which uses read to wait fo= r the
>> watch. And in the same time, the program tries to read some value,=
>> but actually it hangs at sending the command (before even sending = a path to be
>> read). Strace gives this (simplified for readability):
>> [pid=C2=A0 2494] write(3, "\4\0\0\0\0\0\0\0\0\0\0\0\f\0\0\0&q= uot;, 160 =3D 16
>> [pid=C2=A0 2494] write(3, "domid\0", 6)=C2=A0 =C2=A0 =C2= =A0 =3D 6
>> [pid=C2=A0 2494] write(3, "token\0", 6)=C2=A0 =C2=A0 =C2= =A0 =3D 6
>> [pid=C2=A0 2495] read(3,=C2=A0 <unfinished ...>
>> [pid=C2=A0 2494] futex(0x71c0d4, FUTEX_WAIT_PRIVATE, 1, NULL <u= nfinished ...>
>> [pid=C2=A0 2495] <... read resumed>
>> "\17\0\0\0\377\377\377\377\220~\255\27\f\0\0\0", 16) =3D= 16
>> [pid=C2=A0 2495] read(3, "domid\0token\0", 12) =3D 12 >> [pid=C2=A0 2495] read(3, "\4\0\0\0\0\0\0\0\0\0\0\0\3\0\0\0&qu= ot;, 16) =3D 16
>> [pid=C2=A0 2495] read(3, "OK\0", 3)=C2=A0 =C2=A0 =C2=A0 = =C2=A0 =C2=A0 =3D 3
>> [pid=C2=A0 2495] futex(0x71c0d4, FUTEX_WAKE_OP_PRIVATE, 1, 1, 0x71= c0d0,
>> {FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 1} <unfinished ...>
>> [pid=C2=A0 2494] <... futex resumed> )=C2=A0 =C2=A0 =C2=A0 = =C2=A0=3D 0
>> [pid=C2=A0 2495] <... futex resumed> )=C2=A0 =C2=A0 =C2=A0 = =C2=A0=3D 1
>> [pid=C2=A0 2494] futex(0x71c0a8, FUTEX_WAIT_PRIVATE, 2, NULL <u= nfinished ...>
>> [pid=C2=A0 2495] futex(0x71c0a8, FUTEX_WAKE_PRIVATE, 1 <unfinis= hed ...>
>> [pid=C2=A0 2494] <... futex resumed> )=C2=A0 =C2=A0 =C2=A0 = =C2=A0=3D -1 EAGAIN (Resource
>> temporarily unavailable)
>> [pid=C2=A0 2495] <... futex resumed> )=C2=A0 =C2=A0 =C2=A0 = =C2=A0=3D 0
>> [pid=C2=A0 2494] futex(0x71c0a8, FUTEX_WAKE_PRIVATE, 1 <unfinis= hed ...>
>> [pid=C2=A0 2495] read(3,=C2=A0 <unfinished ...>
>> [pid=C2=A0 2494] <... futex resumed> )=C2=A0 =C2=A0 =C2=A0 = =C2=A0=3D 0
>> [pid=C2=A0 2494] rt_sigaction(SIGPIPE, {SIG_DFL, [], SA_RESTORER,<= br> >> 0x7fc78c1488f0}, NULL, 8) =3D 0
>> [pid=C2=A0 2494] rt_sigaction(SIGPIPE, {SIG_IGN, [], SA_RESTORER,<= br> >> 0x7fc78c1488f0}, {SIG_DFL, [], SA_RESTORER, 0x7fc78c1488f0}, 8) = =3D 0
>> [pid=C2=A0 2494] write(3, "\2\0\0\0\0\0\0\0\0\0\0\0\5\0\0\0&q= uot;, 16
>>
>> And thats all - 2494 is waiting on write, 2495 is waiting on read.=
>>
>> On 3.12.x it is working. On 3.17.0 and 3.18.7 it is broken. I have= n't
>> checked versions in the middle.
>>
>> Any ideas?
>>
>> _______________________________________________
>> Xen-devel mailing list
>> Xen-devel@lists.xen.org=
>> http:= //lists.xen.org/xen-devel
>
>

_______________________________________________
Embedded-pv-devel mailing list
Embedded-pv-devel= @lists.xenproject.org
http://lists.xenproject.org/cgi-bin/mailman/listi= nfo/embedded-pv-devel


=
--
Vitaly Chernooky |=C2=A0Senior = Developer - Product Engineering and Development
Global= Logic
P +380.44.4929695 ext.1136 M +380.63.6011802=C2=A0S cvv_2k
<= div>
--001a11354880f6c28b0511a365f7-- --===============2416449970709874428== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============2416449970709874428==-- From embedded-pv-devel-bounces@lists.xenproject.org Thu Mar 19 13:10:57 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Thu, 19 Mar 2015 13:10:57 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYaDw-0005vq-Ho; Thu, 19 Mar 2015 13:10:56 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYaDu-0005vY-Dl for Embedded-pv-devel@lists.xenproject.org; Thu, 19 Mar 2015 13:10:54 +0000 Received: from [85.158.137.68] by server-15.bemta-3.messagelabs.com id FB/79-10326-DDACA055; Thu, 19 Mar 2015 13:10:53 +0000 X-Env-Sender: vitalii.chernookyi@globallogic.com X-Msg-Ref: server-15.tower-31.messagelabs.com!1426770650!13564279!1 X-Originating-IP: [64.18.0.20] X-SpamReason: No, hits=0.9 required=7.0 tests=HTML_40_50,HTML_MESSAGE, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 3458 invoked from network); 19 Mar 2015 13:10:52 -0000 Received: from exprod5og110.obsmtp.com (HELO exprod5og110.obsmtp.com) (64.18.0.20) by server-15.tower-31.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 19 Mar 2015 13:10:52 -0000 Received: from mail-qg0-f46.google.com ([209.85.192.46]) (using TLSv1) by exprod5ob110.postini.com ([64.18.4.12]) with SMTP ID DSNKVQrK2Uw/bUAVYYpmd8pjed8ELvheFXG0@postini.com; Thu, 19 Mar 2015 06:10:51 PDT Received: by qgez64 with SMTP id z64so64063573qge.2 for ; Thu, 19 Mar 2015 06:10:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=iIemm6cinK7+MduhyT5Nxi5EZKpxlKwYkZm+MJKcQkw=; b=ISoHPP1NT4Bdp6txPDunibWX7SqTdaviuD6ABVaw1F6Yu0NkszWgK0X/EJNdTEIyjJ vbYxhH7VBOWNM16zm2SBmdqrvywkN/0caqH2hxiwqMpFLCkSQW7vqIpp9HXJL/MofCNW 3/Rw/Ay0CKx5DRgl5K8oAlzmMGSq3yuXhux1s= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=iIemm6cinK7+MduhyT5Nxi5EZKpxlKwYkZm+MJKcQkw=; b=OEmCIyTOE5VR3lsiT6VISnssLlAzveYxUTGgTOsvG6VTtpHTO2AY4s8ja3ZH0Ycz5r bvEzaV6n1+ACfn/89n3lPT0OKfXAIG+6qiKmPbbR6xPh8Zch/m31AtBmUhMMJwJ0Xl2m EdDEOfZ2HLvUDTE4yfsUcHU3hVfOpysuOFsgCKdewux+eSRsKL7hew3fSeWjrQvtpKl2 HBF7mReZTfjk2yuGuOXVNbRI+GX/mS3Rnh7L62WmY6bSwiYy//xyJom7ll84bBqcYM2O N+RrGq/DGT2nn3EjwLeJs+VSHb2CRqgiDVEB0YUUNnlewPLFPwMrbF9DQv2/UEdhj7ED 1iow== X-Gm-Message-State: ALoCoQmxGpDrY3ysGH7iduYhwbsS3AH7hPwwQJXoVTmEbz46D7rSltWacsjCAckOq+GF++KV6MNOjH9S05PJeB1PCj/KNRPWPx8plg3grHiCWd/o2epjmlXyS+fekw2XX60VphrHqxfbDWnoZMeTrQimz7ZQPN8MgCzA3K9I5XEy47F8rbCed2Y= X-Received: by 10.140.42.195 with SMTP id c61mr61916890qga.94.1426770649220; Thu, 19 Mar 2015 06:10:49 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.140.42.195 with SMTP id c61mr61916868qga.94.1426770649104; Thu, 19 Mar 2015 06:10:49 -0700 (PDT) Received: by 10.140.98.145 with HTTP; Thu, 19 Mar 2015 06:10:49 -0700 (PDT) In-Reply-To: <550AC883.40008@citrix.com> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> Date: Thu, 19 Mar 2015 15:10:49 +0200 Message-ID: From: Vitaly Chernooky To: David Vrabel Cc: Iurii Konovalenko , Ian Campbell , =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= , xen-devel , Embedded-pv-devel@lists.xenproject.org, Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============9052969402650839727==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============9052969402650839727== Content-Type: multipart/alternative; boundary=001a113abef4b7794b0511a3ed42 --001a113abef4b7794b0511a3ed42 Content-Type: text/plain; charset=UTF-8 David, On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel wrote: > On 19/03/15 12:10, Iurii Konovalenko wrote: > > Hi, guys! > > > > When I read, that I am not alone and that issue depends on kernel > > version, I decided to continue investigation. > > And I found why our threads locks on read/write operations. > > On Linux kernel 3.14+ syscalls of file read and write changed a bit: > > fdget() function was replaced by fdget_pos() - it is fdget() function > > plus additional position mutex lock for files with FMODE_ATOMIC_POS > > (files for inodes with S_IFREG flag set - regular nodes). As I thought > > our xen files are not regular and nonseekable, I hoped this flag is > > not set. But it is set. It is because our file system is created by > > function simple_fill_super(), and inside it this flag is hardly set: > > inode->i_mode = S_IFREG | files->mode; > > So, as a fast hack I made a patch: just made copy of this function for > > xen, which does not set this flag. It works for me. Could you please > > check if it works for you. > > I still can't get this to deadlock, but why not clear FMODE_ATOMIC_POS > in xenbus_file_open() ? > Because it is not the root of issue. FMODE_ATOMIC_POS is just one of results of bug. Iurii has fixed the root of issue but in suboptimal way. So we just need to have found optimal way. With best regards, > David > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel > -- *Vitaly Chernooky | Senior Developer - Product Engineering and Development* GlobalLogic P *+380.44.4929695 ext.1136* M *+380.63.6011802* S cvv_2k www.globallogic.com http://www.globallogic.com/email_disclaimer.txt --001a113abef4b7794b0511a3ed42 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
David,

On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel &= lt;david.vrabe= l@citrix.com> wrote:
On = 19/03/15 12:10, Iurii Konovalenko wrote:
> Hi, guys!
>
> When I read, that I am not alone and that issue depends on kernel
> version, I decided to continue investigation.
> And I found why our threads locks on read/write operations.
> On Linux kernel 3.14+ syscalls of file read and write changed a bit: > fdget() function was replaced by fdget_pos() - it is fdget() function<= br> > plus additional position mutex lock for files with FMODE_ATOMIC_POS > (files for inodes with S_IFREG flag set - regular nodes). As I thought=
> our xen files are not regular and nonseekable, I hoped this flag is > not set. But it is set. It is because our file system is created by > function simple_fill_super(), and inside it this flag is hardly set: > inode->i_mode =3D S_IFREG | files->mode;
> So, as a fast hack I made a patch: just made copy of this function for=
> xen, which does not set this flag. It works for me. Could you please > check if it works for you.

I still can't get this to deadlock, but why not clear FMODE_ATOM= IC_POS
in xenbus_file_open() ?

Because it is n= ot the root of issue.=C2=A0FMODE_ATOMIC_POS is just one of results of bug. = Iurii has fixed the root of issue but in suboptimal way. So we just need to= have found optimal way.

With best regards,
<= div>=C2=A0
D= avid


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.x= en.org/xen-devel



--
=
= Vitaly Chernooky |=C2=A0Senior Developer - Produ= ct Engineering and Development
GlobalLogic
P= +380.44.4929695 ext.1136 M +380.63.6011802=C2=A0S cvv_2k

http://www.globallogic.com/email_disclaimer.txt
<= /div>
--001a113abef4b7794b0511a3ed42-- --===============9052969402650839727== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============9052969402650839727==-- From embedded-pv-devel-bounces@lists.xenproject.org Thu Mar 19 13:10:57 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Thu, 19 Mar 2015 13:10:57 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYaDw-0005vq-Ho; Thu, 19 Mar 2015 13:10:56 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYaDu-0005vY-Dl for Embedded-pv-devel@lists.xenproject.org; Thu, 19 Mar 2015 13:10:54 +0000 Received: from [85.158.137.68] by server-15.bemta-3.messagelabs.com id FB/79-10326-DDACA055; Thu, 19 Mar 2015 13:10:53 +0000 X-Env-Sender: vitalii.chernookyi@globallogic.com X-Msg-Ref: server-15.tower-31.messagelabs.com!1426770650!13564279!1 X-Originating-IP: [64.18.0.20] X-SpamReason: No, hits=0.9 required=7.0 tests=HTML_40_50,HTML_MESSAGE, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 3458 invoked from network); 19 Mar 2015 13:10:52 -0000 Received: from exprod5og110.obsmtp.com (HELO exprod5og110.obsmtp.com) (64.18.0.20) by server-15.tower-31.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 19 Mar 2015 13:10:52 -0000 Received: from mail-qg0-f46.google.com ([209.85.192.46]) (using TLSv1) by exprod5ob110.postini.com ([64.18.4.12]) with SMTP ID DSNKVQrK2Uw/bUAVYYpmd8pjed8ELvheFXG0@postini.com; Thu, 19 Mar 2015 06:10:51 PDT Received: by qgez64 with SMTP id z64so64063573qge.2 for ; Thu, 19 Mar 2015 06:10:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=iIemm6cinK7+MduhyT5Nxi5EZKpxlKwYkZm+MJKcQkw=; b=ISoHPP1NT4Bdp6txPDunibWX7SqTdaviuD6ABVaw1F6Yu0NkszWgK0X/EJNdTEIyjJ vbYxhH7VBOWNM16zm2SBmdqrvywkN/0caqH2hxiwqMpFLCkSQW7vqIpp9HXJL/MofCNW 3/Rw/Ay0CKx5DRgl5K8oAlzmMGSq3yuXhux1s= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=iIemm6cinK7+MduhyT5Nxi5EZKpxlKwYkZm+MJKcQkw=; b=OEmCIyTOE5VR3lsiT6VISnssLlAzveYxUTGgTOsvG6VTtpHTO2AY4s8ja3ZH0Ycz5r bvEzaV6n1+ACfn/89n3lPT0OKfXAIG+6qiKmPbbR6xPh8Zch/m31AtBmUhMMJwJ0Xl2m EdDEOfZ2HLvUDTE4yfsUcHU3hVfOpysuOFsgCKdewux+eSRsKL7hew3fSeWjrQvtpKl2 HBF7mReZTfjk2yuGuOXVNbRI+GX/mS3Rnh7L62WmY6bSwiYy//xyJom7ll84bBqcYM2O N+RrGq/DGT2nn3EjwLeJs+VSHb2CRqgiDVEB0YUUNnlewPLFPwMrbF9DQv2/UEdhj7ED 1iow== X-Gm-Message-State: ALoCoQmxGpDrY3ysGH7iduYhwbsS3AH7hPwwQJXoVTmEbz46D7rSltWacsjCAckOq+GF++KV6MNOjH9S05PJeB1PCj/KNRPWPx8plg3grHiCWd/o2epjmlXyS+fekw2XX60VphrHqxfbDWnoZMeTrQimz7ZQPN8MgCzA3K9I5XEy47F8rbCed2Y= X-Received: by 10.140.42.195 with SMTP id c61mr61916890qga.94.1426770649220; Thu, 19 Mar 2015 06:10:49 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.140.42.195 with SMTP id c61mr61916868qga.94.1426770649104; Thu, 19 Mar 2015 06:10:49 -0700 (PDT) Received: by 10.140.98.145 with HTTP; Thu, 19 Mar 2015 06:10:49 -0700 (PDT) In-Reply-To: <550AC883.40008@citrix.com> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> Date: Thu, 19 Mar 2015 15:10:49 +0200 Message-ID: From: Vitaly Chernooky To: David Vrabel Cc: Iurii Konovalenko , Ian Campbell , =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= , xen-devel , Embedded-pv-devel@lists.xenproject.org, Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============9052969402650839727==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============9052969402650839727== Content-Type: multipart/alternative; boundary=001a113abef4b7794b0511a3ed42 --001a113abef4b7794b0511a3ed42 Content-Type: text/plain; charset=UTF-8 David, On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel wrote: > On 19/03/15 12:10, Iurii Konovalenko wrote: > > Hi, guys! > > > > When I read, that I am not alone and that issue depends on kernel > > version, I decided to continue investigation. > > And I found why our threads locks on read/write operations. > > On Linux kernel 3.14+ syscalls of file read and write changed a bit: > > fdget() function was replaced by fdget_pos() - it is fdget() function > > plus additional position mutex lock for files with FMODE_ATOMIC_POS > > (files for inodes with S_IFREG flag set - regular nodes). As I thought > > our xen files are not regular and nonseekable, I hoped this flag is > > not set. But it is set. It is because our file system is created by > > function simple_fill_super(), and inside it this flag is hardly set: > > inode->i_mode = S_IFREG | files->mode; > > So, as a fast hack I made a patch: just made copy of this function for > > xen, which does not set this flag. It works for me. Could you please > > check if it works for you. > > I still can't get this to deadlock, but why not clear FMODE_ATOMIC_POS > in xenbus_file_open() ? > Because it is not the root of issue. FMODE_ATOMIC_POS is just one of results of bug. Iurii has fixed the root of issue but in suboptimal way. So we just need to have found optimal way. With best regards, > David > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel > -- *Vitaly Chernooky | Senior Developer - Product Engineering and Development* GlobalLogic P *+380.44.4929695 ext.1136* M *+380.63.6011802* S cvv_2k www.globallogic.com http://www.globallogic.com/email_disclaimer.txt --001a113abef4b7794b0511a3ed42 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
David,

On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel &= lt;david.vrabe= l@citrix.com> wrote:
On = 19/03/15 12:10, Iurii Konovalenko wrote:
> Hi, guys!
>
> When I read, that I am not alone and that issue depends on kernel
> version, I decided to continue investigation.
> And I found why our threads locks on read/write operations.
> On Linux kernel 3.14+ syscalls of file read and write changed a bit: > fdget() function was replaced by fdget_pos() - it is fdget() function<= br> > plus additional position mutex lock for files with FMODE_ATOMIC_POS > (files for inodes with S_IFREG flag set - regular nodes). As I thought=
> our xen files are not regular and nonseekable, I hoped this flag is > not set. But it is set. It is because our file system is created by > function simple_fill_super(), and inside it this flag is hardly set: > inode->i_mode =3D S_IFREG | files->mode;
> So, as a fast hack I made a patch: just made copy of this function for=
> xen, which does not set this flag. It works for me. Could you please > check if it works for you.

I still can't get this to deadlock, but why not clear FMODE_ATOM= IC_POS
in xenbus_file_open() ?

Because it is n= ot the root of issue.=C2=A0FMODE_ATOMIC_POS is just one of results of bug. = Iurii has fixed the root of issue but in suboptimal way. So we just need to= have found optimal way.

With best regards,
<= div>=C2=A0
D= avid


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.x= en.org/xen-devel



--
=
= Vitaly Chernooky |=C2=A0Senior Developer - Produ= ct Engineering and Development
GlobalLogic
P= +380.44.4929695 ext.1136 M +380.63.6011802=C2=A0S cvv_2k

http://www.globallogic.com/email_disclaimer.txt
<= /div>
--001a113abef4b7794b0511a3ed42-- --===============9052969402650839727== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============9052969402650839727==-- From embedded-pv-devel-bounces@lists.xenproject.org Thu Mar 19 18:17:41 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Thu, 19 Mar 2015 18:17:41 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYf0m-0005eg-TX; Thu, 19 Mar 2015 18:17:40 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYa4J-0003Zf-U6 for Embedded-pv-devel@lists.xenproject.org; Thu, 19 Mar 2015 13:01:00 +0000 Received: from [85.158.139.211] by server-6.bemta-5.messagelabs.com id 4C/61-01116-B88CA055; Thu, 19 Mar 2015 13:00:59 +0000 X-Env-Sender: david.vrabel@citrix.com X-Msg-Ref: server-16.tower-206.messagelabs.com!1426770056!8978471!1 X-Originating-IP: [66.165.176.89] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni44OSA9PiAyMDMwMDc=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 31043 invoked from network); 19 Mar 2015 13:00:58 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-16.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 19 Mar 2015 13:00:58 -0000 X-IronPort-AV: E=Sophos;i="5.11,429,1422921600"; d="scan'208";a="244911472" Message-ID: <550AC883.40008@citrix.com> Date: Thu, 19 Mar 2015 13:00:51 +0000 From: David Vrabel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.4.0 MIME-Version: 1.0 To: Iurii Konovalenko , Ian Campbell References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> In-Reply-To: X-DLP: MIA1 X-Mailman-Approved-At: Thu, 19 Mar 2015 18:17:39 +0000 Cc: Embedded-pv-devel@lists.xenproject.org, Boris Ostrovsky , xen-devel , David Vrabel , =?windows-1252?Q?Marek_Marczyk?= =?windows-1252?Q?owski-G=F3recki?= Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org On 19/03/15 12:10, Iurii Konovalenko wrote: > Hi, guys! > > When I read, that I am not alone and that issue depends on kernel > version, I decided to continue investigation. > And I found why our threads locks on read/write operations. > On Linux kernel 3.14+ syscalls of file read and write changed a bit: > fdget() function was replaced by fdget_pos() - it is fdget() function > plus additional position mutex lock for files with FMODE_ATOMIC_POS > (files for inodes with S_IFREG flag set - regular nodes). As I thought > our xen files are not regular and nonseekable, I hoped this flag is > not set. But it is set. It is because our file system is created by > function simple_fill_super(), and inside it this flag is hardly set: > inode->i_mode = S_IFREG | files->mode; > So, as a fast hack I made a patch: just made copy of this function for > xen, which does not set this flag. It works for me. Could you please > check if it works for you. I still can't get this to deadlock, but why not clear FMODE_ATOMIC_POS in xenbus_file_open() ? David _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Thu Mar 19 18:17:41 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Thu, 19 Mar 2015 18:17:41 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYf0m-0005eg-TX; Thu, 19 Mar 2015 18:17:40 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYa4J-0003Zf-U6 for Embedded-pv-devel@lists.xenproject.org; Thu, 19 Mar 2015 13:01:00 +0000 Received: from [85.158.139.211] by server-6.bemta-5.messagelabs.com id 4C/61-01116-B88CA055; Thu, 19 Mar 2015 13:00:59 +0000 X-Env-Sender: david.vrabel@citrix.com X-Msg-Ref: server-16.tower-206.messagelabs.com!1426770056!8978471!1 X-Originating-IP: [66.165.176.89] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni44OSA9PiAyMDMwMDc=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 31043 invoked from network); 19 Mar 2015 13:00:58 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-16.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 19 Mar 2015 13:00:58 -0000 X-IronPort-AV: E=Sophos;i="5.11,429,1422921600"; d="scan'208";a="244911472" Message-ID: <550AC883.40008@citrix.com> Date: Thu, 19 Mar 2015 13:00:51 +0000 From: David Vrabel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.4.0 MIME-Version: 1.0 To: Iurii Konovalenko , Ian Campbell References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> In-Reply-To: X-DLP: MIA1 X-Mailman-Approved-At: Thu, 19 Mar 2015 18:17:39 +0000 Cc: Embedded-pv-devel@lists.xenproject.org, Boris Ostrovsky , xen-devel , David Vrabel , =?windows-1252?Q?Marek_Marczyk?= =?windows-1252?Q?owski-G=F3recki?= Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org On 19/03/15 12:10, Iurii Konovalenko wrote: > Hi, guys! > > When I read, that I am not alone and that issue depends on kernel > version, I decided to continue investigation. > And I found why our threads locks on read/write operations. > On Linux kernel 3.14+ syscalls of file read and write changed a bit: > fdget() function was replaced by fdget_pos() - it is fdget() function > plus additional position mutex lock for files with FMODE_ATOMIC_POS > (files for inodes with S_IFREG flag set - regular nodes). As I thought > our xen files are not regular and nonseekable, I hoped this flag is > not set. But it is set. It is because our file system is created by > function simple_fill_super(), and inside it this flag is hardly set: > inode->i_mode = S_IFREG | files->mode; > So, as a fast hack I made a patch: just made copy of this function for > xen, which does not set this flag. It works for me. Could you please > check if it works for you. I still can't get this to deadlock, but why not clear FMODE_ATOMIC_POS in xenbus_file_open() ? David _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 09:58:43 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 09:58:43 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYthT-0006mk-6y; Fri, 20 Mar 2015 09:58:43 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYthR-0006mH-Fq for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 09:58:41 +0000 Received: from [85.158.137.68] by server-2.bemta-3.messagelabs.com id 1B/E0-21485-05FEB055; Fri, 20 Mar 2015 09:58:40 +0000 X-Env-Sender: vitalii.chernookyi@globallogic.com X-Msg-Ref: server-4.tower-31.messagelabs.com!1426845516!13918125!1 X-Originating-IP: [64.18.0.186] X-SpamReason: No, hits=1.4 required=7.0 tests=BODY_RANDOM_LONG, HTML_40_50,HTML_MESSAGE,RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 14244 invoked from network); 20 Mar 2015 09:58:39 -0000 Received: from exprod5og108.obsmtp.com (HELO exprod5og108.obsmtp.com) (64.18.0.186) by server-4.tower-31.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 20 Mar 2015 09:58:39 -0000 Received: from mail-qg0-f48.google.com ([209.85.192.48]) (using TLSv1) by exprod5ob108.postini.com ([64.18.4.12]) with SMTP ID DSNKVQvvS8ozhcZHq+C/qKmfOpmHn1YC/lNJ@postini.com; Fri, 20 Mar 2015 02:58:38 PDT Received: by qgf3 with SMTP id 3so87976087qgf.3 for ; Fri, 20 Mar 2015 02:58:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=1yJ8hMxK7HHi4yNaPeIPoPwZy/uWUUuwQZXu6Vk0idA=; b=IluLvA6HKDeh1sn39eeZG0+4ywBg8+7XfKY0X2dHDeKfJArpPqGOtfaNieTAre7DnT gEqQ9UM3BfCdvQZkUiLi0pOJ7facePQYU/H3MRoVMI0KpJwdQ70CxzuxsWDvd/y1P4ld puiRsYylBjlR9FmIryfdLPPZyyItbYhsvlIzA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=1yJ8hMxK7HHi4yNaPeIPoPwZy/uWUUuwQZXu6Vk0idA=; b=aBhoeAFFnESRl7CdnRWLAM3+og/8OBXDPnbaI3jnN/Kppncw+wK8m4RBt4x7RZtCJF Vw5U3IJSyGHYfZl99dsQjbDtVv3RV7PD6+ipiHeQ+FA5f6USds4YSnQLztdDuRXxNumE 5fCGq1qHG/lZ0p0oWUPnS8wkoRrwQaage3H3cqq3T1CFHSwWLO5yapXCjoMH1tp0LVAa KLZQ++zLrWyalu+MQ16IHblGEOiAO5JbWPPyMFbM69YapN0oEcUkB9/Ja2Fl6dxxShJO eesvxM77fG685kS/4Cow5iek66fypsZCrnreRgqwC3RHH9qc3PEplCMyKqHYGhA9ijwp 2ZDQ== X-Gm-Message-State: ALoCoQnwPPnPUvNIlUo6aPa4AW6BxMcWcsuIG56XYI5tA/J/xn3p/ndnWjYqMbzK1q/4AhbvRidqLXTocCn/1mrw4f3BDMGOhtqJgRaw+QFtsJ4W0RCTjx6pnF2NTqsnZGCRqTI2y5sZRwxBPoNxfUBTw6Oi2MznizHGKcmdsTofajmvi1eX3g8= X-Received: by 10.55.31.97 with SMTP id f94mr114697640qkf.10.1426845515456; Fri, 20 Mar 2015 02:58:35 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.55.31.97 with SMTP id f94mr114697633qkf.10.1426845515370; Fri, 20 Mar 2015 02:58:35 -0700 (PDT) Received: by 10.140.98.145 with HTTP; Fri, 20 Mar 2015 02:58:35 -0700 (PDT) In-Reply-To: <20150320040454.GZ2321@mail-itl> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> <20150320040454.GZ2321@mail-itl> Date: Fri, 20 Mar 2015 11:58:35 +0200 Message-ID: From: Vitaly Chernooky To: =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= Cc: Iurii Konovalenko , Ian Campbell , xen-devel , Embedded-pv-devel@lists.xenproject.org, David Vrabel , Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============5875354011197157815==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============5875354011197157815== Content-Type: multipart/alternative; boundary=001a1147ec1e17eb3a0511b55c37 --001a1147ec1e17eb3a0511b55c37 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3=B3recki < marmarek@invisiblethingslab.com> wrote: > On Thu, Mar 19, 2015 at 03:10:49PM +0200, Vitaly Chernooky wrote: > > David, > > > > On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel > > wrote: > > > > > On 19/03/15 12:10, Iurii Konovalenko wrote: > > > > Hi, guys! > > > > > > > > When I read, that I am not alone and that issue depends on kernel > > > > version, I decided to continue investigation. > > > > And I found why our threads locks on read/write operations. > > > > On Linux kernel 3.14+ syscalls of file read and write changed a bit= : > > > > fdget() function was replaced by fdget_pos() - it is fdget() functi= on > > > > plus additional position mutex lock for files with FMODE_ATOMIC_POS > > > > (files for inodes with S_IFREG flag set - regular nodes). As I > thought > > > > our xen files are not regular and nonseekable, I hoped this flag is > > > > not set. But it is set. It is because our file system is created by > > > > function simple_fill_super(), and inside it this flag is hardly set= : > > > > inode->i_mode =3D S_IFREG | files->mode; > > > > So, as a fast hack I made a patch: just made copy of this function > for > > > > xen, which does not set this flag. It works for me. Could you pleas= e > > > > check if it works for you. > > > > > > I still can't get this to deadlock, but why not clear FMODE_ATOMIC_PO= S > > > in xenbus_file_open() ? > > > > > > > Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > > results of bug. Iurii has fixed the root of issue but in suboptimal way= . > So > > we just need to have found optimal way. > > I can just confirm that: > 1. (unsurprisingly) the bug is still present in 4.0-rc4 > 2. both proposed fixes are effective > > I'm not sure if removing S_IFREG completely is a good idea, I guess > there will be much more side effects... > Hm... Usually nobody expect regular files to be nonseekable, but ... Yes, I am going to recheck it twice in the nearest future. > What about another idea: xenbus_file_open uses nonseekable_open - this > looks like a good place to clear FMODE_ATOMIC_POS if present? It is wrong place to clear FMODE_ATOMIC_POS but something in your idea is right. It > doesn't make sense to get a lock for position on nonseekable file, > right? > Usually :) > > -- > Best Regards, > Marek Marczykowski-G=C3=B3recki > Invisible Things Lab > A: Because it messes up the order in which people normally read text. > Q: Why is top-posting such a bad thing? > --=20 *Vitaly Chernooky | Senior Developer - Product Engineering and Development* GlobalLogic P *+380.44.4929695 ext.1136* M *+380.63.6011802* S cvv_2k www.globallogic.com http://www.globallogic.com/email_disclaimer.txt --001a1147ec1e17eb3a0511b55c37 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable


On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3=B3recki <marmarek@invisiblethingslab.com> wrote:
On Thu, Mar 19, 2015 at 03:10:= 49PM +0200, Vitaly Chernooky wrote:
> David,
>
> On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel <david.vrabel@citrix.com>
> wrote:
>
> > On 19/03/15 12:10, Iurii Konovalenko wrote:
> > > Hi, guys!
> > >
> > > When I read, that I am not alone and that issue depends on k= ernel
> > > version, I decided to continue investigation.
> > > And I found why our threads locks on read/write operations.<= br> > > > On Linux kernel 3.14+ syscalls of file read and write change= d a bit:
> > > fdget() function was replaced by fdget_pos() - it is fdget()= function
> > > plus additional position mutex lock for files with FMODE_ATO= MIC_POS
> > > (files for inodes with S_IFREG flag set - regular nodes). As= I thought
> > > our xen files are not regular and nonseekable, I hoped this = flag is
> > > not set. But it is set. It is because our file system is cre= ated by
> > > function simple_fill_super(), and inside it this flag is har= dly set:
> > > inode->i_mode =3D S_IFREG | files->mode;
> > > So, as a fast hack I made a patch: just made copy of this fu= nction for
> > > xen, which does not set this flag. It works for me. Could yo= u please
> > > check if it works for you.
> >
> > I still can't get this to deadlock, but why not clear FMODE_A= TOMIC_POS
> > in xenbus_file_open() ?
> >
>
> Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > results of bug. Iurii has fixed the root of issue but in suboptimal wa= y. So
> we just need to have found optimal way.

I can just confirm that:
1. (unsurprisingly) the bug is still present in 4.0-rc4
2. both proposed fixes are effective

I'm not sure if removing S_IFREG completely is a good idea, I guess
there will be much more side effects...

Hm... Usually nobody expect regular files to be nonseekable, but ...
Yes, I am going to recheck it twice in the nearest future.
=C2=A0
What about another idea: xenbus_file_open uses nonseekable_open - this
looks like a good place to clear FMODE_ATOMIC_POS if present?
<= div>
It is wrong place to clear =C2=A0FMODE_ATOMIC_POS but so= mething in your idea is right.

It
doesn't make sense to get a lock for position on nonseekable file,
right?

Usually :)
=C2=A0

--
Best Regards,
Marek Marczykowski-G=C3=B3recki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?



--
=
= Vitaly Chernooky |=C2=A0Senior Developer - Produ= ct Engineering and Development
GlobalLogic
P= +380.44.4929695 ext.1136 M +380.63.6011802=C2=A0S cvv_2k

http://www.globallogic.com/email_disclaimer.txt
<= /div>
--001a1147ec1e17eb3a0511b55c37-- --===============5875354011197157815== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============5875354011197157815==-- From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 09:58:43 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 09:58:43 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYthT-0006mk-6y; Fri, 20 Mar 2015 09:58:43 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYthR-0006mH-Fq for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 09:58:41 +0000 Received: from [85.158.137.68] by server-2.bemta-3.messagelabs.com id 1B/E0-21485-05FEB055; Fri, 20 Mar 2015 09:58:40 +0000 X-Env-Sender: vitalii.chernookyi@globallogic.com X-Msg-Ref: server-4.tower-31.messagelabs.com!1426845516!13918125!1 X-Originating-IP: [64.18.0.186] X-SpamReason: No, hits=1.4 required=7.0 tests=BODY_RANDOM_LONG, HTML_40_50,HTML_MESSAGE,RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 14244 invoked from network); 20 Mar 2015 09:58:39 -0000 Received: from exprod5og108.obsmtp.com (HELO exprod5og108.obsmtp.com) (64.18.0.186) by server-4.tower-31.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 20 Mar 2015 09:58:39 -0000 Received: from mail-qg0-f48.google.com ([209.85.192.48]) (using TLSv1) by exprod5ob108.postini.com ([64.18.4.12]) with SMTP ID DSNKVQvvS8ozhcZHq+C/qKmfOpmHn1YC/lNJ@postini.com; Fri, 20 Mar 2015 02:58:38 PDT Received: by qgf3 with SMTP id 3so87976087qgf.3 for ; Fri, 20 Mar 2015 02:58:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=1yJ8hMxK7HHi4yNaPeIPoPwZy/uWUUuwQZXu6Vk0idA=; b=IluLvA6HKDeh1sn39eeZG0+4ywBg8+7XfKY0X2dHDeKfJArpPqGOtfaNieTAre7DnT gEqQ9UM3BfCdvQZkUiLi0pOJ7facePQYU/H3MRoVMI0KpJwdQ70CxzuxsWDvd/y1P4ld puiRsYylBjlR9FmIryfdLPPZyyItbYhsvlIzA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=1yJ8hMxK7HHi4yNaPeIPoPwZy/uWUUuwQZXu6Vk0idA=; b=aBhoeAFFnESRl7CdnRWLAM3+og/8OBXDPnbaI3jnN/Kppncw+wK8m4RBt4x7RZtCJF Vw5U3IJSyGHYfZl99dsQjbDtVv3RV7PD6+ipiHeQ+FA5f6USds4YSnQLztdDuRXxNumE 5fCGq1qHG/lZ0p0oWUPnS8wkoRrwQaage3H3cqq3T1CFHSwWLO5yapXCjoMH1tp0LVAa KLZQ++zLrWyalu+MQ16IHblGEOiAO5JbWPPyMFbM69YapN0oEcUkB9/Ja2Fl6dxxShJO eesvxM77fG685kS/4Cow5iek66fypsZCrnreRgqwC3RHH9qc3PEplCMyKqHYGhA9ijwp 2ZDQ== X-Gm-Message-State: ALoCoQnwPPnPUvNIlUo6aPa4AW6BxMcWcsuIG56XYI5tA/J/xn3p/ndnWjYqMbzK1q/4AhbvRidqLXTocCn/1mrw4f3BDMGOhtqJgRaw+QFtsJ4W0RCTjx6pnF2NTqsnZGCRqTI2y5sZRwxBPoNxfUBTw6Oi2MznizHGKcmdsTofajmvi1eX3g8= X-Received: by 10.55.31.97 with SMTP id f94mr114697640qkf.10.1426845515456; Fri, 20 Mar 2015 02:58:35 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.55.31.97 with SMTP id f94mr114697633qkf.10.1426845515370; Fri, 20 Mar 2015 02:58:35 -0700 (PDT) Received: by 10.140.98.145 with HTTP; Fri, 20 Mar 2015 02:58:35 -0700 (PDT) In-Reply-To: <20150320040454.GZ2321@mail-itl> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> <20150320040454.GZ2321@mail-itl> Date: Fri, 20 Mar 2015 11:58:35 +0200 Message-ID: From: Vitaly Chernooky To: =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= Cc: Iurii Konovalenko , Ian Campbell , xen-devel , Embedded-pv-devel@lists.xenproject.org, David Vrabel , Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============5875354011197157815==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============5875354011197157815== Content-Type: multipart/alternative; boundary=001a1147ec1e17eb3a0511b55c37 --001a1147ec1e17eb3a0511b55c37 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3=B3recki < marmarek@invisiblethingslab.com> wrote: > On Thu, Mar 19, 2015 at 03:10:49PM +0200, Vitaly Chernooky wrote: > > David, > > > > On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel > > wrote: > > > > > On 19/03/15 12:10, Iurii Konovalenko wrote: > > > > Hi, guys! > > > > > > > > When I read, that I am not alone and that issue depends on kernel > > > > version, I decided to continue investigation. > > > > And I found why our threads locks on read/write operations. > > > > On Linux kernel 3.14+ syscalls of file read and write changed a bit= : > > > > fdget() function was replaced by fdget_pos() - it is fdget() functi= on > > > > plus additional position mutex lock for files with FMODE_ATOMIC_POS > > > > (files for inodes with S_IFREG flag set - regular nodes). As I > thought > > > > our xen files are not regular and nonseekable, I hoped this flag is > > > > not set. But it is set. It is because our file system is created by > > > > function simple_fill_super(), and inside it this flag is hardly set= : > > > > inode->i_mode =3D S_IFREG | files->mode; > > > > So, as a fast hack I made a patch: just made copy of this function > for > > > > xen, which does not set this flag. It works for me. Could you pleas= e > > > > check if it works for you. > > > > > > I still can't get this to deadlock, but why not clear FMODE_ATOMIC_PO= S > > > in xenbus_file_open() ? > > > > > > > Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > > results of bug. Iurii has fixed the root of issue but in suboptimal way= . > So > > we just need to have found optimal way. > > I can just confirm that: > 1. (unsurprisingly) the bug is still present in 4.0-rc4 > 2. both proposed fixes are effective > > I'm not sure if removing S_IFREG completely is a good idea, I guess > there will be much more side effects... > Hm... Usually nobody expect regular files to be nonseekable, but ... Yes, I am going to recheck it twice in the nearest future. > What about another idea: xenbus_file_open uses nonseekable_open - this > looks like a good place to clear FMODE_ATOMIC_POS if present? It is wrong place to clear FMODE_ATOMIC_POS but something in your idea is right. It > doesn't make sense to get a lock for position on nonseekable file, > right? > Usually :) > > -- > Best Regards, > Marek Marczykowski-G=C3=B3recki > Invisible Things Lab > A: Because it messes up the order in which people normally read text. > Q: Why is top-posting such a bad thing? > --=20 *Vitaly Chernooky | Senior Developer - Product Engineering and Development* GlobalLogic P *+380.44.4929695 ext.1136* M *+380.63.6011802* S cvv_2k www.globallogic.com http://www.globallogic.com/email_disclaimer.txt --001a1147ec1e17eb3a0511b55c37 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable


On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3=B3recki <marmarek@invisiblethingslab.com> wrote:
On Thu, Mar 19, 2015 at 03:10:= 49PM +0200, Vitaly Chernooky wrote:
> David,
>
> On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel <david.vrabel@citrix.com>
> wrote:
>
> > On 19/03/15 12:10, Iurii Konovalenko wrote:
> > > Hi, guys!
> > >
> > > When I read, that I am not alone and that issue depends on k= ernel
> > > version, I decided to continue investigation.
> > > And I found why our threads locks on read/write operations.<= br> > > > On Linux kernel 3.14+ syscalls of file read and write change= d a bit:
> > > fdget() function was replaced by fdget_pos() - it is fdget()= function
> > > plus additional position mutex lock for files with FMODE_ATO= MIC_POS
> > > (files for inodes with S_IFREG flag set - regular nodes). As= I thought
> > > our xen files are not regular and nonseekable, I hoped this = flag is
> > > not set. But it is set. It is because our file system is cre= ated by
> > > function simple_fill_super(), and inside it this flag is har= dly set:
> > > inode->i_mode =3D S_IFREG | files->mode;
> > > So, as a fast hack I made a patch: just made copy of this fu= nction for
> > > xen, which does not set this flag. It works for me. Could yo= u please
> > > check if it works for you.
> >
> > I still can't get this to deadlock, but why not clear FMODE_A= TOMIC_POS
> > in xenbus_file_open() ?
> >
>
> Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > results of bug. Iurii has fixed the root of issue but in suboptimal wa= y. So
> we just need to have found optimal way.

I can just confirm that:
1. (unsurprisingly) the bug is still present in 4.0-rc4
2. both proposed fixes are effective

I'm not sure if removing S_IFREG completely is a good idea, I guess
there will be much more side effects...

Hm... Usually nobody expect regular files to be nonseekable, but ...
Yes, I am going to recheck it twice in the nearest future.
=C2=A0
What about another idea: xenbus_file_open uses nonseekable_open - this
looks like a good place to clear FMODE_ATOMIC_POS if present?
<= div>
It is wrong place to clear =C2=A0FMODE_ATOMIC_POS but so= mething in your idea is right.

It
doesn't make sense to get a lock for position on nonseekable file,
right?

Usually :)
=C2=A0

--
Best Regards,
Marek Marczykowski-G=C3=B3recki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?



--
=
= Vitaly Chernooky |=C2=A0Senior Developer - Produ= ct Engineering and Development
GlobalLogic
P= +380.44.4929695 ext.1136 M +380.63.6011802=C2=A0S cvv_2k

http://www.globallogic.com/email_disclaimer.txt
<= /div>
--001a1147ec1e17eb3a0511b55c37-- --===============5875354011197157815== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============5875354011197157815==-- From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 10:08:56 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 10:08:56 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYtrM-0000jN-Cl; Fri, 20 Mar 2015 10:08:56 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYtrL-0000im-1y for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 10:08:55 +0000 Received: from [85.158.139.211] by server-1.bemta-5.messagelabs.com id 71/58-11927-6B1FB055; Fri, 20 Mar 2015 10:08:54 +0000 X-Env-Sender: vitalii.chernookyi@globallogic.com X-Msg-Ref: server-10.tower-206.messagelabs.com!1426846129!6797044!1 X-Originating-IP: [64.18.0.189] X-SpamReason: No, hits=0.4 required=7.0 tests=HTML_30_40,HTML_MESSAGE, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 19504 invoked from network); 20 Mar 2015 10:08:51 -0000 Received: from exprod5og119.obsmtp.com (HELO exprod5og119.obsmtp.com) (64.18.0.189) by server-10.tower-206.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 20 Mar 2015 10:08:51 -0000 Received: from mail-qg0-f45.google.com ([209.85.192.45]) (using TLSv1) by exprod5ob119.postini.com ([64.18.4.12]) with SMTP ID DSNKVQvxsVUM6K7tIpIkxjXNE2ED059Xud0C@postini.com; Fri, 20 Mar 2015 03:08:51 PDT Received: by qgfa8 with SMTP id a8so88343404qgf.0 for ; Fri, 20 Mar 2015 03:08:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=5ia3mBIXw9pytcHvwCOzuqUOHrnEE6XPtthq5qhbj0E=; b=LgKfcXMONVR7E8ngvrY0v4hoE6AM5yfXa9M8ZstydiLOLn1wR3wPnmYVdQS4V+6c+W 3/KXXqIRMk7YIC7oK9VLYSV/RpEYZxtwS0sWufOrfaAceiqL/LY6IygYm5z0WDFuifnB yS9bh5pMGBAJQ+y1yoyW+cWLo5JpgZEJqrWoA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=5ia3mBIXw9pytcHvwCOzuqUOHrnEE6XPtthq5qhbj0E=; b=SfevRXFaKXKjngQ0O8aNSjr+Y67aBQiVuIciz2qgLV0FFPUgLxxHLB4lvrWyzohdJh hGl9EUg1B10uAiMOery/1q7ygFQeFfrjp5/+IYuxssziH+/uMq6uwgSMI7ztYgL94vC0 MrK+uPvOxumozXnv4vWvbm+lGpPLxA4AD+eW101Sci0Qy5CwM1jXdjk8yjKWPOSYAEFJ i8HcGZB0hrQLwRyhYfzJNCIa5e73v8AHQKwl4tSSU7pajQ/F0W9j0mfO1gmFsO98+9iR RFqJDdVntCCWZM3nb/AqHoWnDxvPTPNBTqgF3jLsv6XlgcNmKz2trzgDMp20Y33dTP6s kSpw== X-Gm-Message-State: ALoCoQnJbQInpcazWG+QE7sgeo4Ukyj+401Qz7aS/d4KbEbxqGeKFKHp+LL8tfmH9pUOMvqX/9o1/qvcD3FIdVnjT7fEnQXwohJ4UPRZ9XTsURBBawbDNjXcXPQnDzsy06JNIblx50ANw7aPhPngzTZfp9nx1ggY1+voapUMXRgE6U3uUKXrUCQ= X-Received: by 10.55.40.135 with SMTP id o7mr127441688qko.93.1426846128914; Fri, 20 Mar 2015 03:08:48 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.55.40.135 with SMTP id o7mr127441667qko.93.1426846128805; Fri, 20 Mar 2015 03:08:48 -0700 (PDT) Received: by 10.140.98.145 with HTTP; Fri, 20 Mar 2015 03:08:48 -0700 (PDT) In-Reply-To: <20150320040454.GZ2321@mail-itl> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> <20150320040454.GZ2321@mail-itl> Date: Fri, 20 Mar 2015 12:08:48 +0200 Message-ID: From: Vitaly Chernooky To: =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= Cc: Iurii Konovalenko , Ian Campbell , xen-devel , Embedded-pv-devel@lists.xenproject.org, David Vrabel , Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1620903624199217199==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============1620903624199217199== Content-Type: multipart/alternative; boundary=001a1142a4a2a828290511b580f5 --001a1142a4a2a828290511b580f5 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3=B3recki < marmarek@invisiblethingslab.com> wrote: > On Thu, Mar 19, 2015 at 03:10:49PM +0200, Vitaly Chernooky wrote: > > David, > > > > On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel > > wrote: > > > > > On 19/03/15 12:10, Iurii Konovalenko wrote: > > > > Hi, guys! > > > > > > > > When I read, that I am not alone and that issue depends on kernel > > > > version, I decided to continue investigation. > > > > And I found why our threads locks on read/write operations. > > > > On Linux kernel 3.14+ syscalls of file read and write changed a bit= : > > > > fdget() function was replaced by fdget_pos() - it is fdget() functi= on > > > > plus additional position mutex lock for files with FMODE_ATOMIC_POS > > > > (files for inodes with S_IFREG flag set - regular nodes). As I > thought > > > > our xen files are not regular and nonseekable, I hoped this flag is > > > > not set. But it is set. It is because our file system is created by > > > > function simple_fill_super(), and inside it this flag is hardly set= : > > > > inode->i_mode =3D S_IFREG | files->mode; > > > > So, as a fast hack I made a patch: just made copy of this function > for > > > > xen, which does not set this flag. It works for me. Could you pleas= e > > > > check if it works for you. > > > > > > I still can't get this to deadlock, but why not clear FMODE_ATOMIC_PO= S > > > in xenbus_file_open() ? > > > > > > > Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > > results of bug. Iurii has fixed the root of issue but in suboptimal way= . > So > > we just need to have found optimal way. > > I can just confirm that: > 1. (unsurprisingly) the bug is still present in 4.0-rc4 > 2. both proposed fixes are effective > > I'm not sure if removing S_IFREG completely is a good idea, I guess > there will be much more side effects... > What about another idea: xenbus_file_open uses nonseekable_open - this > looks like a good place to clear FMODE_ATOMIC_POS if present? It > doesn't make sense to get a lock for position on nonseekable file, > right? > The Open Group Base Specifications Issue 7 IEEE Std 1003.1, 2013 Edition requires from regular files to be seekable. But Linux kernel looks like Linus has own opinion on it :((( With best regards, > -- > Best Regards, > Marek Marczykowski-G=C3=B3recki > Invisible Things Lab > A: Because it messes up the order in which people normally read text. > Q: Why is top-posting such a bad thing? > --=20 *Vitaly Chernooky | Senior Developer - Product Engineering and Development* GlobalLogic P *+380.44.4929695 ext.1136* M *+380.63.6011802* S cvv_2k www.globallogic.com http://www.globallogic.com/email_disclaimer.txt --001a1142a4a2a828290511b580f5 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable


On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3=B3recki <marmarek@invisiblethingslab.com> wrote:
On Thu, Mar 19, 2015 at 03:10:= 49PM +0200, Vitaly Chernooky wrote:
> David,
>
> On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel <david.vrabel@citrix.com>
> wrote:
>
> > On 19/03/15 12:10, Iurii Konovalenko wrote:
> > > Hi, guys!
> > >
> > > When I read, that I am not alone and that issue depends on k= ernel
> > > version, I decided to continue investigation.
> > > And I found why our threads locks on read/write operations.<= br> > > > On Linux kernel 3.14+ syscalls of file read and write change= d a bit:
> > > fdget() function was replaced by fdget_pos() - it is fdget()= function
> > > plus additional position mutex lock for files with FMODE_ATO= MIC_POS
> > > (files for inodes with S_IFREG flag set - regular nodes). As= I thought
> > > our xen files are not regular and nonseekable, I hoped this = flag is
> > > not set. But it is set. It is because our file system is cre= ated by
> > > function simple_fill_super(), and inside it this flag is har= dly set:
> > > inode->i_mode =3D S_IFREG | files->mode;
> > > So, as a fast hack I made a patch: just made copy of this fu= nction for
> > > xen, which does not set this flag. It works for me. Could yo= u please
> > > check if it works for you.
> >
> > I still can't get this to deadlock, but why not clear FMODE_A= TOMIC_POS
> > in xenbus_file_open() ?
> >
>
> Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > results of bug. Iurii has fixed the root of issue but in suboptimal wa= y. So
> we just need to have found optimal way.

I can just confirm that:
1. (unsurprisingly) the bug is still present in 4.0-rc4
2. both proposed fixes are effective

I'm not sure if removing S_IFREG completely is a good idea, I guess
there will be much more side effects...
What about another idea: xenbus_file_open uses nonseekable_open - this
looks like a good place to clear FMODE_ATOMIC_POS if present? It
doesn't make sense to get a lock for position on nonseekable file,
right?

The Open Group Base Specif= ications Issue 7=C2=A0IEEE Std 1003.1, 2013 Edition requires from regular f= iles to be seekable. But Linux kernel looks like Linus has own opinion on i= t :(((

With best reg= ards,
=C2=A0
--
Best Regards,
Marek Marczykowski-G=C3=B3recki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?



--
=
= Vitaly Chernooky |=C2=A0Senior Developer - Produ= ct Engineering and Development
GlobalLogic
P= +380.44.4929695 ext.1136 M +380.63.6011802=C2=A0S cvv_2k

http://www.globallogic.com/email_disclaimer.txt
<= /div>
--001a1142a4a2a828290511b580f5-- --===============1620903624199217199== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============1620903624199217199==-- From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 10:08:56 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 10:08:56 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYtrM-0000jN-Cl; Fri, 20 Mar 2015 10:08:56 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYtrL-0000im-1y for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 10:08:55 +0000 Received: from [85.158.139.211] by server-1.bemta-5.messagelabs.com id 71/58-11927-6B1FB055; Fri, 20 Mar 2015 10:08:54 +0000 X-Env-Sender: vitalii.chernookyi@globallogic.com X-Msg-Ref: server-10.tower-206.messagelabs.com!1426846129!6797044!1 X-Originating-IP: [64.18.0.189] X-SpamReason: No, hits=0.4 required=7.0 tests=HTML_30_40,HTML_MESSAGE, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 19504 invoked from network); 20 Mar 2015 10:08:51 -0000 Received: from exprod5og119.obsmtp.com (HELO exprod5og119.obsmtp.com) (64.18.0.189) by server-10.tower-206.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 20 Mar 2015 10:08:51 -0000 Received: from mail-qg0-f45.google.com ([209.85.192.45]) (using TLSv1) by exprod5ob119.postini.com ([64.18.4.12]) with SMTP ID DSNKVQvxsVUM6K7tIpIkxjXNE2ED059Xud0C@postini.com; Fri, 20 Mar 2015 03:08:51 PDT Received: by qgfa8 with SMTP id a8so88343404qgf.0 for ; Fri, 20 Mar 2015 03:08:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=5ia3mBIXw9pytcHvwCOzuqUOHrnEE6XPtthq5qhbj0E=; b=LgKfcXMONVR7E8ngvrY0v4hoE6AM5yfXa9M8ZstydiLOLn1wR3wPnmYVdQS4V+6c+W 3/KXXqIRMk7YIC7oK9VLYSV/RpEYZxtwS0sWufOrfaAceiqL/LY6IygYm5z0WDFuifnB yS9bh5pMGBAJQ+y1yoyW+cWLo5JpgZEJqrWoA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=5ia3mBIXw9pytcHvwCOzuqUOHrnEE6XPtthq5qhbj0E=; b=SfevRXFaKXKjngQ0O8aNSjr+Y67aBQiVuIciz2qgLV0FFPUgLxxHLB4lvrWyzohdJh hGl9EUg1B10uAiMOery/1q7ygFQeFfrjp5/+IYuxssziH+/uMq6uwgSMI7ztYgL94vC0 MrK+uPvOxumozXnv4vWvbm+lGpPLxA4AD+eW101Sci0Qy5CwM1jXdjk8yjKWPOSYAEFJ i8HcGZB0hrQLwRyhYfzJNCIa5e73v8AHQKwl4tSSU7pajQ/F0W9j0mfO1gmFsO98+9iR RFqJDdVntCCWZM3nb/AqHoWnDxvPTPNBTqgF3jLsv6XlgcNmKz2trzgDMp20Y33dTP6s kSpw== X-Gm-Message-State: ALoCoQnJbQInpcazWG+QE7sgeo4Ukyj+401Qz7aS/d4KbEbxqGeKFKHp+LL8tfmH9pUOMvqX/9o1/qvcD3FIdVnjT7fEnQXwohJ4UPRZ9XTsURBBawbDNjXcXPQnDzsy06JNIblx50ANw7aPhPngzTZfp9nx1ggY1+voapUMXRgE6U3uUKXrUCQ= X-Received: by 10.55.40.135 with SMTP id o7mr127441688qko.93.1426846128914; Fri, 20 Mar 2015 03:08:48 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.55.40.135 with SMTP id o7mr127441667qko.93.1426846128805; Fri, 20 Mar 2015 03:08:48 -0700 (PDT) Received: by 10.140.98.145 with HTTP; Fri, 20 Mar 2015 03:08:48 -0700 (PDT) In-Reply-To: <20150320040454.GZ2321@mail-itl> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> <20150320040454.GZ2321@mail-itl> Date: Fri, 20 Mar 2015 12:08:48 +0200 Message-ID: From: Vitaly Chernooky To: =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= Cc: Iurii Konovalenko , Ian Campbell , xen-devel , Embedded-pv-devel@lists.xenproject.org, David Vrabel , Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1620903624199217199==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============1620903624199217199== Content-Type: multipart/alternative; boundary=001a1142a4a2a828290511b580f5 --001a1142a4a2a828290511b580f5 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3=B3recki < marmarek@invisiblethingslab.com> wrote: > On Thu, Mar 19, 2015 at 03:10:49PM +0200, Vitaly Chernooky wrote: > > David, > > > > On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel > > wrote: > > > > > On 19/03/15 12:10, Iurii Konovalenko wrote: > > > > Hi, guys! > > > > > > > > When I read, that I am not alone and that issue depends on kernel > > > > version, I decided to continue investigation. > > > > And I found why our threads locks on read/write operations. > > > > On Linux kernel 3.14+ syscalls of file read and write changed a bit= : > > > > fdget() function was replaced by fdget_pos() - it is fdget() functi= on > > > > plus additional position mutex lock for files with FMODE_ATOMIC_POS > > > > (files for inodes with S_IFREG flag set - regular nodes). As I > thought > > > > our xen files are not regular and nonseekable, I hoped this flag is > > > > not set. But it is set. It is because our file system is created by > > > > function simple_fill_super(), and inside it this flag is hardly set= : > > > > inode->i_mode =3D S_IFREG | files->mode; > > > > So, as a fast hack I made a patch: just made copy of this function > for > > > > xen, which does not set this flag. It works for me. Could you pleas= e > > > > check if it works for you. > > > > > > I still can't get this to deadlock, but why not clear FMODE_ATOMIC_PO= S > > > in xenbus_file_open() ? > > > > > > > Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > > results of bug. Iurii has fixed the root of issue but in suboptimal way= . > So > > we just need to have found optimal way. > > I can just confirm that: > 1. (unsurprisingly) the bug is still present in 4.0-rc4 > 2. both proposed fixes are effective > > I'm not sure if removing S_IFREG completely is a good idea, I guess > there will be much more side effects... > What about another idea: xenbus_file_open uses nonseekable_open - this > looks like a good place to clear FMODE_ATOMIC_POS if present? It > doesn't make sense to get a lock for position on nonseekable file, > right? > The Open Group Base Specifications Issue 7 IEEE Std 1003.1, 2013 Edition requires from regular files to be seekable. But Linux kernel looks like Linus has own opinion on it :((( With best regards, > -- > Best Regards, > Marek Marczykowski-G=C3=B3recki > Invisible Things Lab > A: Because it messes up the order in which people normally read text. > Q: Why is top-posting such a bad thing? > --=20 *Vitaly Chernooky | Senior Developer - Product Engineering and Development* GlobalLogic P *+380.44.4929695 ext.1136* M *+380.63.6011802* S cvv_2k www.globallogic.com http://www.globallogic.com/email_disclaimer.txt --001a1142a4a2a828290511b580f5 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable


On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3=B3recki <marmarek@invisiblethingslab.com> wrote:
On Thu, Mar 19, 2015 at 03:10:= 49PM +0200, Vitaly Chernooky wrote:
> David,
>
> On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel <david.vrabel@citrix.com>
> wrote:
>
> > On 19/03/15 12:10, Iurii Konovalenko wrote:
> > > Hi, guys!
> > >
> > > When I read, that I am not alone and that issue depends on k= ernel
> > > version, I decided to continue investigation.
> > > And I found why our threads locks on read/write operations.<= br> > > > On Linux kernel 3.14+ syscalls of file read and write change= d a bit:
> > > fdget() function was replaced by fdget_pos() - it is fdget()= function
> > > plus additional position mutex lock for files with FMODE_ATO= MIC_POS
> > > (files for inodes with S_IFREG flag set - regular nodes). As= I thought
> > > our xen files are not regular and nonseekable, I hoped this = flag is
> > > not set. But it is set. It is because our file system is cre= ated by
> > > function simple_fill_super(), and inside it this flag is har= dly set:
> > > inode->i_mode =3D S_IFREG | files->mode;
> > > So, as a fast hack I made a patch: just made copy of this fu= nction for
> > > xen, which does not set this flag. It works for me. Could yo= u please
> > > check if it works for you.
> >
> > I still can't get this to deadlock, but why not clear FMODE_A= TOMIC_POS
> > in xenbus_file_open() ?
> >
>
> Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > results of bug. Iurii has fixed the root of issue but in suboptimal wa= y. So
> we just need to have found optimal way.

I can just confirm that:
1. (unsurprisingly) the bug is still present in 4.0-rc4
2. both proposed fixes are effective

I'm not sure if removing S_IFREG completely is a good idea, I guess
there will be much more side effects...
What about another idea: xenbus_file_open uses nonseekable_open - this
looks like a good place to clear FMODE_ATOMIC_POS if present? It
doesn't make sense to get a lock for position on nonseekable file,
right?

The Open Group Base Specif= ications Issue 7=C2=A0IEEE Std 1003.1, 2013 Edition requires from regular f= iles to be seekable. But Linux kernel looks like Linus has own opinion on i= t :(((

With best reg= ards,
=C2=A0
--
Best Regards,
Marek Marczykowski-G=C3=B3recki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?



--
=
= Vitaly Chernooky |=C2=A0Senior Developer - Produ= ct Engineering and Development
GlobalLogic
P= +380.44.4929695 ext.1136 M +380.63.6011802=C2=A0S cvv_2k

http://www.globallogic.com/email_disclaimer.txt
<= /div>
--001a1142a4a2a828290511b580f5-- --===============1620903624199217199== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============1620903624199217199==-- From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 10:38:11 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 10:38:11 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYuJe-0007Ku-QU; Fri, 20 Mar 2015 10:38:10 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYuJd-0007Kk-Cx for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 10:38:09 +0000 Received: from [85.158.137.68] by server-2.bemta-3.messagelabs.com id 44/F3-21485-098FB055; Fri, 20 Mar 2015 10:38:08 +0000 X-Env-Sender: vitalii.chernookyi@globallogic.com X-Msg-Ref: server-12.tower-31.messagelabs.com!1426847883!13917999!1 X-Originating-IP: [64.18.0.28] X-SpamReason: No, hits=0.9 required=7.0 tests=HTML_40_50,HTML_MESSAGE, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 13774 invoked from network); 20 Mar 2015 10:38:06 -0000 Received: from exprod5og114.obsmtp.com (HELO exprod5og114.obsmtp.com) (64.18.0.28) by server-12.tower-31.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 20 Mar 2015 10:38:06 -0000 Received: from mail-qc0-f174.google.com ([209.85.216.174]) (using TLSv1) by exprod5ob114.postini.com ([64.18.4.12]) with SMTP ID DSNKVQv4i+DlbF99QKYYWEPDFqr6Z24l1pn2@postini.com; Fri, 20 Mar 2015 03:38:06 PDT Received: by qcaz10 with SMTP id z10so89467602qca.1 for ; Fri, 20 Mar 2015 03:38:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=PlLxMz8mdGUwAEb+Bry9JIWgxOetbNngOGCSfkcIZD8=; b=bdHAPPULKW8/f4mBN9t1gVpnT0RhLtJ/34fwYcgK/eReEgQ5CvnAMaZq8s1LQMYoZb IqceTEJiIfNokAvdenvvSY+1aUGzFJ0v278EhjGZ2t6FkkgodE78sCLMEOicvtF+eILk cdvOZKW6u41jUQqLX4EiebLNK/5C315hiKNTY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=PlLxMz8mdGUwAEb+Bry9JIWgxOetbNngOGCSfkcIZD8=; b=fwMp66DIBp8oG9Z1qosmIwoOJskMe3dAt1IUCLHOb/b170sITAB8L9ldfDjdrxyy8e MrEZgUjwIJIBGFyN2XRSZDIGRNHYf8MIWgunfruMc9XCN5WlC/RgsVDufdM/weS+PrFr Hm6MVNGk7CTAql+eMx2kMvXPlDSCvyJqGMTYJj+ol6i/2FCi56LZVrpPPv+64AwUddxX L+KfDfrHsDkh845ayDAInCPnuY7lbXoKJHEI+vVZiZ0UNdSGhiTJg5EbaftdyPc2K1pu 6pFILWU2ajBq5kFu6VrlB9Oxkp4ho550OcNWNovh686eNY1t7+avCQxwEBewyevD7qzl 42qA== X-Gm-Message-State: ALoCoQlfLh1b3KLX1NJDZVbG43J5HMD8GRGRrpNJy58SJxxqZcr7zE1ctumY0fJlm+Wm4t6fS4NlbbUnEEo3n7JhAiAa8reMK5PzgM5bd+h11chKNKSiqPVuaYA2Rarx4tU0ZjXz3A4iCyi4QpbpNQBapYtUpKcTsStHitiw4cZihu8ERaT4kL8= X-Received: by 10.55.22.30 with SMTP id g30mr124763547qkh.54.1426847882809; Fri, 20 Mar 2015 03:38:02 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.55.22.30 with SMTP id g30mr124763533qkh.54.1426847882675; Fri, 20 Mar 2015 03:38:02 -0700 (PDT) Received: by 10.140.98.145 with HTTP; Fri, 20 Mar 2015 03:38:02 -0700 (PDT) In-Reply-To: References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> <20150320040454.GZ2321@mail-itl> Date: Fri, 20 Mar 2015 12:38:02 +0200 Message-ID: From: Vitaly Chernooky To: =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= Content-Type: multipart/mixed; boundary=001a1147a89c326ad20511b5e9ef Cc: Iurii Konovalenko , Ian Campbell , xen-devel , Embedded-pv-devel@lists.xenproject.org, David Vrabel , Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --001a1147a89c326ad20511b5e9ef Content-Type: multipart/alternative; boundary=001a1147a89c326acf0511b5e9ed --001a1147a89c326acf0511b5e9ed Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable So I have finished my investigation and suggest to discuss the simple attaches patch. With best regards, On Fri, Mar 20, 2015 at 12:08 PM, Vitaly Chernooky < vitalii.chernookyi@globallogic.com> wrote: > > > On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3=B3recki < > marmarek@invisiblethingslab.com> wrote: > >> On Thu, Mar 19, 2015 at 03:10:49PM +0200, Vitaly Chernooky wrote: >> > David, >> > >> > On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel >> > wrote: >> > >> > > On 19/03/15 12:10, Iurii Konovalenko wrote: >> > > > Hi, guys! >> > > > >> > > > When I read, that I am not alone and that issue depends on kernel >> > > > version, I decided to continue investigation. >> > > > And I found why our threads locks on read/write operations. >> > > > On Linux kernel 3.14+ syscalls of file read and write changed a bi= t: >> > > > fdget() function was replaced by fdget_pos() - it is fdget() >> function >> > > > plus additional position mutex lock for files with FMODE_ATOMIC_PO= S >> > > > (files for inodes with S_IFREG flag set - regular nodes). As I >> thought >> > > > our xen files are not regular and nonseekable, I hoped this flag i= s >> > > > not set. But it is set. It is because our file system is created b= y >> > > > function simple_fill_super(), and inside it this flag is hardly se= t: >> > > > inode->i_mode =3D S_IFREG | files->mode; >> > > > So, as a fast hack I made a patch: just made copy of this function >> for >> > > > xen, which does not set this flag. It works for me. Could you plea= se >> > > > check if it works for you. >> > > >> > > I still can't get this to deadlock, but why not clear FMODE_ATOMIC_P= OS >> > > in xenbus_file_open() ? >> > > >> > >> > Because it is not the root of issue. FMODE_ATOMIC_POS is just one of >> > results of bug. Iurii has fixed the root of issue but in suboptimal >> way. So >> > we just need to have found optimal way. >> >> I can just confirm that: >> 1. (unsurprisingly) the bug is still present in 4.0-rc4 >> 2. both proposed fixes are effective >> >> I'm not sure if removing S_IFREG completely is a good idea, I guess >> there will be much more side effects... >> What about another idea: xenbus_file_open uses nonseekable_open - this >> looks like a good place to clear FMODE_ATOMIC_POS if present? It >> doesn't make sense to get a lock for position on nonseekable file, >> right? >> > > The Open Group Base Specifications Issue 7 IEEE Std 1003.1, 2013 Edition > requires from regular files to be seekable. But Linux kernel looks like > Linus has own opinion on it :((( > > With best regards, > > >> -- >> Best Regards, >> Marek Marczykowski-G=C3=B3recki >> Invisible Things Lab >> A: Because it messes up the order in which people normally read text. >> Q: Why is top-posting such a bad thing? >> > > > > -- > *Vitaly Chernooky | Senior Developer - Product Engineering and Developmen= t* > GlobalLogic > P *+380.44.4929695 ext.1136 <%2B380.44.4929695%20ext.1136>* M *+380.63.60= 11802 > <%2B380.63.6011802>* S cvv_2k > www.globallogic.com > > http://www.globallogic.com/email_disclaimer.txt > --=20 *Vitaly Chernooky | Senior Developer - Product Engineering and Development* GlobalLogic P *+380.44.4929695 ext.1136* M *+380.63.6011802* S cvv_2k www.globallogic.com http://www.globallogic.com/email_disclaimer.txt --001a1147a89c326acf0511b5e9ed Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
So I have finished my investigation and suggest to discuss= the simple attaches patch.

With best regards,

On Fri, Mar 20,= 2015 at 12:08 PM, Vitaly Chernooky <vitalii.chernookyi@g= loballogic.com> wrote:


= On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3= =B3recki <marmarek@invisiblethingslab.com> wro= te:
On Thu, Mar= 19, 2015 at 03:10:49PM +0200, Vitaly Chernooky wrote:
> David,
>
> On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel <david.vrabel@citrix.com> > wrote:
>
> > On 19/03/15 12:10, Iurii Konovalenko wrote:
> > > Hi, guys!
> > >
> > > When I read, that I am not alone and that issue depends on k= ernel
> > > version, I decided to continue investigation.
> > > And I found why our threads locks on read/write operations.<= br> > > > On Linux kernel 3.14+ syscalls of file read and write change= d a bit:
> > > fdget() function was replaced by fdget_pos() - it is fdget()= function
> > > plus additional position mutex lock for files with FMODE_ATO= MIC_POS
> > > (files for inodes with S_IFREG flag set - regular nodes). As= I thought
> > > our xen files are not regular and nonseekable, I hoped this = flag is
> > > not set. But it is set. It is because our file system is cre= ated by
> > > function simple_fill_super(), and inside it this flag is har= dly set:
> > > inode->i_mode =3D S_IFREG | files->mode;
> > > So, as a fast hack I made a patch: just made copy of this fu= nction for
> > > xen, which does not set this flag. It works for me. Could yo= u please
> > > check if it works for you.
> >
> > I still can't get this to deadlock, but why not clear FMODE_A= TOMIC_POS
> > in xenbus_file_open() ?
> >
>
> Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > results of bug. Iurii has fixed the root of issue but in suboptimal wa= y. So
> we just need to have found optimal way.

I can just confirm that:
1. (unsurprisingly) the bug is still present in 4.0-rc4
2. both proposed fixes are effective

I'm not sure if removing S_IFREG completely is a good idea, I guess
there will be much more side effects...
What about another idea: xenbus_file_open uses nonseekable_open - this
looks like a good place to clear FMODE_ATOMIC_POS if present? It
doesn't make sense to get a lock for position on nonseekable file,
right?

The Open Group= Base Specifications Issue 7=C2=A0IEEE Std 1003.1, 2013 Edition requires fr= om regular files to be seekable. But Linux kernel looks like Linus has own = opinion on it :(((

W= ith best regards,
=C2=A0
--
Best Regards,
Marek Marczykowski-G=C3=B3recki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?



--
Vitaly Chernooky |=C2=A0Senior Developer - Product= Engineering and Development
GlobalLogic
P <= font color=3D"#0000ff">+380.44.4929695 ext.1136 M +380.63.6011802=C2=A0S cvv_2k



--
--001a1147a89c326acf0511b5e9ed-- --001a1147a89c326ad20511b5e9ef Content-Type: text/x-patch; charset=US-ASCII; name="0001-Fix-deadlock-on-regular-nonseekable-files.patch" Content-Disposition: attachment; filename="0001-Fix-deadlock-on-regular-nonseekable-files.patch" Content-Transfer-Encoding: base64 X-Attachment-Id: f_i7hgdula0 RnJvbSBmNWY1OTIyZjM4OWMwYjZhMmYwZjkxMmFkZjBjMDkxZWU5N2UwMDc2IE1vbiBTZXAgMTcg MDA6MDA6MDAgMjAwMQpGcm9tOiBWaXRhbHkgQ2hlcm5vb2t5IDx2aXRhbHkuY2hlcm5vb2t5QGds b2JhbGxvZ2ljLmNvbT4KRGF0ZTogRnJpLCAyMCBNYXIgMjAxNSAxMjoyNjozNyArMDIwMApTdWJq ZWN0OiBbUEFUQ0hdIEZpeCBkZWFkbG9jayBvbiByZWd1bGFyIG5vbnNlZWthYmxlIGZpbGVzCgpJ dCBpcyBhY3R1YWwgZm9yIHByb2MtbGlrZSBwc2V1ZG8gZmlsZXN5c3RlbXMgd2hpY2ggbWFyayB0 aGVpciBmaWxlcyBhcwpyZWd1bGFyIGJ1dCBub25zZWVrYWJsZS4KCkNoYW5nZS1JZDogSTkyZjRk YTIyYTU4MzVjYzZiNjM5Njk4OGMzNmI1OTA2NTYxYWM3NDEKU2lnbmVkLW9mZi1ieTogVml0YWx5 IENoZXJub29reSA8dml0YWx5LmNoZXJub29reUBnbG9iYWxsb2dpYy5jb20+Ci0tLQogZnMvb3Bl bi5jIHwgICAgMiArLQogMSBmaWxlIGNoYW5nZWQsIDEgaW5zZXJ0aW9uKCspLCAxIGRlbGV0aW9u KC0pCgpkaWZmIC0tZ2l0IGEvZnMvb3Blbi5jIGIvZnMvb3Blbi5jCmluZGV4IDJlZDczMjUuLmI3 OTI3ODQgMTAwNjQ0Ci0tLSBhL2ZzL29wZW4uYworKysgYi9mcy9vcGVuLmMKQEAgLTExMDAsNyAr MTEwMCw3IEBAIEVYUE9SVF9TWU1CT0woZ2VuZXJpY19maWxlX29wZW4pOwogICovCiBpbnQgbm9u c2Vla2FibGVfb3BlbihzdHJ1Y3QgaW5vZGUgKmlub2RlLCBzdHJ1Y3QgZmlsZSAqZmlscCkKIHsK LQlmaWxwLT5mX21vZGUgJj0gfihGTU9ERV9MU0VFSyB8IEZNT0RFX1BSRUFEIHwgRk1PREVfUFdS SVRFKTsKKwlmaWxwLT5mX21vZGUgJj0gfihGTU9ERV9MU0VFSyB8IEZNT0RFX1BSRUFEIHwgRk1P REVfUFdSSVRFIHwgRk1PREVfQVRPTUlDX1BPUyk7CiAJcmV0dXJuIDA7CiB9CiAKLS0gCjEuNy45 LjUKCg== --001a1147a89c326ad20511b5e9ef Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --001a1147a89c326ad20511b5e9ef-- From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 10:38:11 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 10:38:11 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYuJe-0007Ku-QU; Fri, 20 Mar 2015 10:38:10 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYuJd-0007Kk-Cx for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 10:38:09 +0000 Received: from [85.158.137.68] by server-2.bemta-3.messagelabs.com id 44/F3-21485-098FB055; Fri, 20 Mar 2015 10:38:08 +0000 X-Env-Sender: vitalii.chernookyi@globallogic.com X-Msg-Ref: server-12.tower-31.messagelabs.com!1426847883!13917999!1 X-Originating-IP: [64.18.0.28] X-SpamReason: No, hits=0.9 required=7.0 tests=HTML_40_50,HTML_MESSAGE, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 13774 invoked from network); 20 Mar 2015 10:38:06 -0000 Received: from exprod5og114.obsmtp.com (HELO exprod5og114.obsmtp.com) (64.18.0.28) by server-12.tower-31.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 20 Mar 2015 10:38:06 -0000 Received: from mail-qc0-f174.google.com ([209.85.216.174]) (using TLSv1) by exprod5ob114.postini.com ([64.18.4.12]) with SMTP ID DSNKVQv4i+DlbF99QKYYWEPDFqr6Z24l1pn2@postini.com; Fri, 20 Mar 2015 03:38:06 PDT Received: by qcaz10 with SMTP id z10so89467602qca.1 for ; Fri, 20 Mar 2015 03:38:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=PlLxMz8mdGUwAEb+Bry9JIWgxOetbNngOGCSfkcIZD8=; b=bdHAPPULKW8/f4mBN9t1gVpnT0RhLtJ/34fwYcgK/eReEgQ5CvnAMaZq8s1LQMYoZb IqceTEJiIfNokAvdenvvSY+1aUGzFJ0v278EhjGZ2t6FkkgodE78sCLMEOicvtF+eILk cdvOZKW6u41jUQqLX4EiebLNK/5C315hiKNTY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=PlLxMz8mdGUwAEb+Bry9JIWgxOetbNngOGCSfkcIZD8=; b=fwMp66DIBp8oG9Z1qosmIwoOJskMe3dAt1IUCLHOb/b170sITAB8L9ldfDjdrxyy8e MrEZgUjwIJIBGFyN2XRSZDIGRNHYf8MIWgunfruMc9XCN5WlC/RgsVDufdM/weS+PrFr Hm6MVNGk7CTAql+eMx2kMvXPlDSCvyJqGMTYJj+ol6i/2FCi56LZVrpPPv+64AwUddxX L+KfDfrHsDkh845ayDAInCPnuY7lbXoKJHEI+vVZiZ0UNdSGhiTJg5EbaftdyPc2K1pu 6pFILWU2ajBq5kFu6VrlB9Oxkp4ho550OcNWNovh686eNY1t7+avCQxwEBewyevD7qzl 42qA== X-Gm-Message-State: ALoCoQlfLh1b3KLX1NJDZVbG43J5HMD8GRGRrpNJy58SJxxqZcr7zE1ctumY0fJlm+Wm4t6fS4NlbbUnEEo3n7JhAiAa8reMK5PzgM5bd+h11chKNKSiqPVuaYA2Rarx4tU0ZjXz3A4iCyi4QpbpNQBapYtUpKcTsStHitiw4cZihu8ERaT4kL8= X-Received: by 10.55.22.30 with SMTP id g30mr124763547qkh.54.1426847882809; Fri, 20 Mar 2015 03:38:02 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.55.22.30 with SMTP id g30mr124763533qkh.54.1426847882675; Fri, 20 Mar 2015 03:38:02 -0700 (PDT) Received: by 10.140.98.145 with HTTP; Fri, 20 Mar 2015 03:38:02 -0700 (PDT) In-Reply-To: References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> <20150320040454.GZ2321@mail-itl> Date: Fri, 20 Mar 2015 12:38:02 +0200 Message-ID: From: Vitaly Chernooky To: =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= Content-Type: multipart/mixed; boundary=001a1147a89c326ad20511b5e9ef Cc: Iurii Konovalenko , Ian Campbell , xen-devel , Embedded-pv-devel@lists.xenproject.org, David Vrabel , Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --001a1147a89c326ad20511b5e9ef Content-Type: multipart/alternative; boundary=001a1147a89c326acf0511b5e9ed --001a1147a89c326acf0511b5e9ed Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable So I have finished my investigation and suggest to discuss the simple attaches patch. With best regards, On Fri, Mar 20, 2015 at 12:08 PM, Vitaly Chernooky < vitalii.chernookyi@globallogic.com> wrote: > > > On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3=B3recki < > marmarek@invisiblethingslab.com> wrote: > >> On Thu, Mar 19, 2015 at 03:10:49PM +0200, Vitaly Chernooky wrote: >> > David, >> > >> > On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel >> > wrote: >> > >> > > On 19/03/15 12:10, Iurii Konovalenko wrote: >> > > > Hi, guys! >> > > > >> > > > When I read, that I am not alone and that issue depends on kernel >> > > > version, I decided to continue investigation. >> > > > And I found why our threads locks on read/write operations. >> > > > On Linux kernel 3.14+ syscalls of file read and write changed a bi= t: >> > > > fdget() function was replaced by fdget_pos() - it is fdget() >> function >> > > > plus additional position mutex lock for files with FMODE_ATOMIC_PO= S >> > > > (files for inodes with S_IFREG flag set - regular nodes). As I >> thought >> > > > our xen files are not regular and nonseekable, I hoped this flag i= s >> > > > not set. But it is set. It is because our file system is created b= y >> > > > function simple_fill_super(), and inside it this flag is hardly se= t: >> > > > inode->i_mode =3D S_IFREG | files->mode; >> > > > So, as a fast hack I made a patch: just made copy of this function >> for >> > > > xen, which does not set this flag. It works for me. Could you plea= se >> > > > check if it works for you. >> > > >> > > I still can't get this to deadlock, but why not clear FMODE_ATOMIC_P= OS >> > > in xenbus_file_open() ? >> > > >> > >> > Because it is not the root of issue. FMODE_ATOMIC_POS is just one of >> > results of bug. Iurii has fixed the root of issue but in suboptimal >> way. So >> > we just need to have found optimal way. >> >> I can just confirm that: >> 1. (unsurprisingly) the bug is still present in 4.0-rc4 >> 2. both proposed fixes are effective >> >> I'm not sure if removing S_IFREG completely is a good idea, I guess >> there will be much more side effects... >> What about another idea: xenbus_file_open uses nonseekable_open - this >> looks like a good place to clear FMODE_ATOMIC_POS if present? It >> doesn't make sense to get a lock for position on nonseekable file, >> right? >> > > The Open Group Base Specifications Issue 7 IEEE Std 1003.1, 2013 Edition > requires from regular files to be seekable. But Linux kernel looks like > Linus has own opinion on it :((( > > With best regards, > > >> -- >> Best Regards, >> Marek Marczykowski-G=C3=B3recki >> Invisible Things Lab >> A: Because it messes up the order in which people normally read text. >> Q: Why is top-posting such a bad thing? >> > > > > -- > *Vitaly Chernooky | Senior Developer - Product Engineering and Developmen= t* > GlobalLogic > P *+380.44.4929695 ext.1136 <%2B380.44.4929695%20ext.1136>* M *+380.63.60= 11802 > <%2B380.63.6011802>* S cvv_2k > www.globallogic.com > > http://www.globallogic.com/email_disclaimer.txt > --=20 *Vitaly Chernooky | Senior Developer - Product Engineering and Development* GlobalLogic P *+380.44.4929695 ext.1136* M *+380.63.6011802* S cvv_2k www.globallogic.com http://www.globallogic.com/email_disclaimer.txt --001a1147a89c326acf0511b5e9ed Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
So I have finished my investigation and suggest to discuss= the simple attaches patch.

With best regards,

On Fri, Mar 20,= 2015 at 12:08 PM, Vitaly Chernooky <vitalii.chernookyi@g= loballogic.com> wrote:


= On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3= =B3recki <marmarek@invisiblethingslab.com> wro= te:
On Thu, Mar= 19, 2015 at 03:10:49PM +0200, Vitaly Chernooky wrote:
> David,
>
> On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel <david.vrabel@citrix.com> > wrote:
>
> > On 19/03/15 12:10, Iurii Konovalenko wrote:
> > > Hi, guys!
> > >
> > > When I read, that I am not alone and that issue depends on k= ernel
> > > version, I decided to continue investigation.
> > > And I found why our threads locks on read/write operations.<= br> > > > On Linux kernel 3.14+ syscalls of file read and write change= d a bit:
> > > fdget() function was replaced by fdget_pos() - it is fdget()= function
> > > plus additional position mutex lock for files with FMODE_ATO= MIC_POS
> > > (files for inodes with S_IFREG flag set - regular nodes). As= I thought
> > > our xen files are not regular and nonseekable, I hoped this = flag is
> > > not set. But it is set. It is because our file system is cre= ated by
> > > function simple_fill_super(), and inside it this flag is har= dly set:
> > > inode->i_mode =3D S_IFREG | files->mode;
> > > So, as a fast hack I made a patch: just made copy of this fu= nction for
> > > xen, which does not set this flag. It works for me. Could yo= u please
> > > check if it works for you.
> >
> > I still can't get this to deadlock, but why not clear FMODE_A= TOMIC_POS
> > in xenbus_file_open() ?
> >
>
> Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > results of bug. Iurii has fixed the root of issue but in suboptimal wa= y. So
> we just need to have found optimal way.

I can just confirm that:
1. (unsurprisingly) the bug is still present in 4.0-rc4
2. both proposed fixes are effective

I'm not sure if removing S_IFREG completely is a good idea, I guess
there will be much more side effects...
What about another idea: xenbus_file_open uses nonseekable_open - this
looks like a good place to clear FMODE_ATOMIC_POS if present? It
doesn't make sense to get a lock for position on nonseekable file,
right?

The Open Group= Base Specifications Issue 7=C2=A0IEEE Std 1003.1, 2013 Edition requires fr= om regular files to be seekable. But Linux kernel looks like Linus has own = opinion on it :(((

W= ith best regards,
=C2=A0
--
Best Regards,
Marek Marczykowski-G=C3=B3recki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?



--
Vitaly Chernooky |=C2=A0Senior Developer - Product= Engineering and Development
GlobalLogic
P <= font color=3D"#0000ff">+380.44.4929695 ext.1136 M +380.63.6011802=C2=A0S cvv_2k



--
--001a1147a89c326acf0511b5e9ed-- --001a1147a89c326ad20511b5e9ef Content-Type: text/x-patch; charset=US-ASCII; name="0001-Fix-deadlock-on-regular-nonseekable-files.patch" Content-Disposition: attachment; filename="0001-Fix-deadlock-on-regular-nonseekable-files.patch" Content-Transfer-Encoding: base64 X-Attachment-Id: f_i7hgdula0 RnJvbSBmNWY1OTIyZjM4OWMwYjZhMmYwZjkxMmFkZjBjMDkxZWU5N2UwMDc2IE1vbiBTZXAgMTcg MDA6MDA6MDAgMjAwMQpGcm9tOiBWaXRhbHkgQ2hlcm5vb2t5IDx2aXRhbHkuY2hlcm5vb2t5QGds b2JhbGxvZ2ljLmNvbT4KRGF0ZTogRnJpLCAyMCBNYXIgMjAxNSAxMjoyNjozNyArMDIwMApTdWJq ZWN0OiBbUEFUQ0hdIEZpeCBkZWFkbG9jayBvbiByZWd1bGFyIG5vbnNlZWthYmxlIGZpbGVzCgpJ dCBpcyBhY3R1YWwgZm9yIHByb2MtbGlrZSBwc2V1ZG8gZmlsZXN5c3RlbXMgd2hpY2ggbWFyayB0 aGVpciBmaWxlcyBhcwpyZWd1bGFyIGJ1dCBub25zZWVrYWJsZS4KCkNoYW5nZS1JZDogSTkyZjRk YTIyYTU4MzVjYzZiNjM5Njk4OGMzNmI1OTA2NTYxYWM3NDEKU2lnbmVkLW9mZi1ieTogVml0YWx5 IENoZXJub29reSA8dml0YWx5LmNoZXJub29reUBnbG9iYWxsb2dpYy5jb20+Ci0tLQogZnMvb3Bl bi5jIHwgICAgMiArLQogMSBmaWxlIGNoYW5nZWQsIDEgaW5zZXJ0aW9uKCspLCAxIGRlbGV0aW9u KC0pCgpkaWZmIC0tZ2l0IGEvZnMvb3Blbi5jIGIvZnMvb3Blbi5jCmluZGV4IDJlZDczMjUuLmI3 OTI3ODQgMTAwNjQ0Ci0tLSBhL2ZzL29wZW4uYworKysgYi9mcy9vcGVuLmMKQEAgLTExMDAsNyAr MTEwMCw3IEBAIEVYUE9SVF9TWU1CT0woZ2VuZXJpY19maWxlX29wZW4pOwogICovCiBpbnQgbm9u c2Vla2FibGVfb3BlbihzdHJ1Y3QgaW5vZGUgKmlub2RlLCBzdHJ1Y3QgZmlsZSAqZmlscCkKIHsK LQlmaWxwLT5mX21vZGUgJj0gfihGTU9ERV9MU0VFSyB8IEZNT0RFX1BSRUFEIHwgRk1PREVfUFdS SVRFKTsKKwlmaWxwLT5mX21vZGUgJj0gfihGTU9ERV9MU0VFSyB8IEZNT0RFX1BSRUFEIHwgRk1P REVfUFdSSVRFIHwgRk1PREVfQVRPTUlDX1BPUyk7CiAJcmV0dXJuIDA7CiB9CiAKLS0gCjEuNy45 LjUKCg== --001a1147a89c326ad20511b5e9ef Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --001a1147a89c326ad20511b5e9ef-- From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 10:47:00 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 10:47:00 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYuSC-00008b-5p; Fri, 20 Mar 2015 10:47:00 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYuSB-00008M-BP for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 10:46:59 +0000 Received: from [85.158.139.211] by server-17.bemta-5.messagelabs.com id 2E/7F-31982-2AAFB055; Fri, 20 Mar 2015 10:46:58 +0000 X-Env-Sender: david.vrabel@citrix.com X-Msg-Ref: server-12.tower-206.messagelabs.com!1426848416!12102339!1 X-Originating-IP: [66.165.176.89] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni44OSA9PiAyMDMwMDc=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 20572 invoked from network); 20 Mar 2015 10:46:57 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-12.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 20 Mar 2015 10:46:57 -0000 X-IronPort-AV: E=Sophos;i="5.11,436,1422921600"; d="scan'208";a="245248555" Message-ID: <550BFA9E.8010102@citrix.com> Date: Fri, 20 Mar 2015 10:46:54 +0000 From: David Vrabel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.4.0 MIME-Version: 1.0 To: Vitaly Chernooky , =?windows-1252?Q?Marek_Marczykowski-G=F3recki?= References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> <20150320040454.GZ2321@mail-itl> In-Reply-To: X-DLP: MIA1 Cc: Boris Ostrovsky , Embedded-pv-devel@lists.xenproject.org, Iurii Konovalenko , Ian Campbell , xen-devel Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org On 20/03/15 10:38, Vitaly Chernooky wrote: > So I have finished my investigation and suggest to discuss the simple > attaches patch. Looks ok to me. But this needs to go via the filesystem maintainers, Cc'ing Linus on it. You should explain the deadlock in more detail in the commit message and mention that it fixes a regression and which commit introduced the regression. Another solution would be to replace the file with a symlink to /dev/xen/xenbus. David _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 10:47:00 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 10:47:00 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYuSC-00008b-5p; Fri, 20 Mar 2015 10:47:00 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYuSB-00008M-BP for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 10:46:59 +0000 Received: from [85.158.139.211] by server-17.bemta-5.messagelabs.com id 2E/7F-31982-2AAFB055; Fri, 20 Mar 2015 10:46:58 +0000 X-Env-Sender: david.vrabel@citrix.com X-Msg-Ref: server-12.tower-206.messagelabs.com!1426848416!12102339!1 X-Originating-IP: [66.165.176.89] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni44OSA9PiAyMDMwMDc=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 20572 invoked from network); 20 Mar 2015 10:46:57 -0000 Received: from smtp.citrix.com (HELO SMTP.CITRIX.COM) (66.165.176.89) by server-12.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 20 Mar 2015 10:46:57 -0000 X-IronPort-AV: E=Sophos;i="5.11,436,1422921600"; d="scan'208";a="245248555" Message-ID: <550BFA9E.8010102@citrix.com> Date: Fri, 20 Mar 2015 10:46:54 +0000 From: David Vrabel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.4.0 MIME-Version: 1.0 To: Vitaly Chernooky , =?windows-1252?Q?Marek_Marczykowski-G=F3recki?= References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> <20150320040454.GZ2321@mail-itl> In-Reply-To: X-DLP: MIA1 Cc: Boris Ostrovsky , Embedded-pv-devel@lists.xenproject.org, Iurii Konovalenko , Ian Campbell , xen-devel Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org On 20/03/15 10:38, Vitaly Chernooky wrote: > So I have finished my investigation and suggest to discuss the simple > attaches patch. Looks ok to me. But this needs to go via the filesystem maintainers, Cc'ing Linus on it. You should explain the deadlock in more detail in the commit message and mention that it fixes a regression and which commit introduced the regression. Another solution would be to replace the file with a symlink to /dev/xen/xenbus. David _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 11:39:11 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 11:39:11 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYvGh-0002Cn-FW; Fri, 20 Mar 2015 11:39:11 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYvGf-00026a-IL for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 11:39:09 +0000 Received: from [193.109.254.147] by server-9.bemta-14.messagelabs.com id C2/6A-17310-9D60C055; Fri, 20 Mar 2015 11:39:05 +0000 X-Env-Sender: vitalii.chernookyi@globallogic.com X-Msg-Ref: server-10.tower-27.messagelabs.com!1426851541!11803953!1 X-Originating-IP: [64.18.0.160] X-SpamReason: No, hits=0.8 required=7.0 tests=BODY_RANDOM_LONG, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.6; banners=-,-,- X-VirusChecked: Checked Received: (qmail 27684 invoked from network); 20 Mar 2015 11:39:02 -0000 Received: from exprod5og118.obsmtp.com (HELO exprod5og118.obsmtp.com) (64.18.0.160) by server-10.tower-27.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 20 Mar 2015 11:39:02 -0000 Received: from mail-qc0-f171.google.com ([209.85.216.171]) (using TLSv1) by exprod5ob118.postini.com ([64.18.4.12]) with SMTP ID DSNKVQwG1B2kXe1biHrG3PhaO3iNAIEP1ngg@postini.com; Fri, 20 Mar 2015 04:39:02 PDT Received: by qcbkw5 with SMTP id kw5so90445147qcb.2 for ; Fri, 20 Mar 2015 04:39:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=Q1HGTelfyIKiQAUAtivYmMwuYABTNZtNS2OGmUS3+S4=; b=gvAX1wX4VrquFn8/b6qz72rz5eHykAPNEmPtYHf4riTbw9NAjGe1gAGypcH/Xb2WZj 0qeZFgfxyBptBeK8GKnHVADmEp6OB6+sZ/rkvJ/B6Rd0cTB2xn+rMTZw5XdNo6hRujYT sOBtPRuhoOKgRY7v0C+g0b4BzKtyDv33ER+ck= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=Q1HGTelfyIKiQAUAtivYmMwuYABTNZtNS2OGmUS3+S4=; b=PcMrKVT07bgUb+grgO+dBnAjZWpwdJuEC/1jA5QfK963lLQ7EwHw7IYP21hhmJnrCX fgHlO9ev8+9fd3HwIBmCT/HoX3fD5XVVtI3Bn0XUPitr9Ig6jEWyZ2Z2m9Do94gFp0SM 9XR4lrUAvQzs6VwqhlrczPT1Hp+gkua8xrH0cNS38vxWyyR44JuTtOEe8MrfGpuEFy8p m82GcJmdHR0O87xew2GLg4obZIkj1nj8kt97SpyCPWFBb3BuDWspRzNADGu0/Ujx/UOs WKgi6UWci7zD6tFe69WCJG0g5cteZ/BjDQpQO2deUB18K+UFOfKEGgNJYCVZSM+x4u9i 2/ug== X-Gm-Message-State: ALoCoQnR4qnU1Etv45pNo8z+MOA8HlyrnWQ+yjAIdSEWoseYnUqJa0zaLttpwNdUEG7Ww9EaxHNWbBxKJPpDvl5tyEsv9GVnuq2Y96xp7YwxmPT80l4kQ1Q9k9rwqBiQ6fi+xW8s5tyfWQxOoIVBcUi//YfNla7rgP75EQRNf+ErvmPAdhLxctk= X-Received: by 10.55.22.30 with SMTP id g30mr125191846qkh.54.1426851540231; Fri, 20 Mar 2015 04:39:00 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.55.22.30 with SMTP id g30mr125191833qkh.54.1426851540130; Fri, 20 Mar 2015 04:39:00 -0700 (PDT) Received: by 10.140.98.145 with HTTP; Fri, 20 Mar 2015 04:39:00 -0700 (PDT) In-Reply-To: <550BFA9E.8010102@citrix.com> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> <20150320040454.GZ2321@mail-itl> <550BFA9E.8010102@citrix.com> Date: Fri, 20 Mar 2015 13:39:00 +0200 Message-ID: From: Vitaly Chernooky To: David Vrabel Cc: Iurii Konovalenko , Ian Campbell , =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= , xen-devel , Embedded-pv-devel@lists.xenproject.org, Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org David, On Fri, Mar 20, 2015 at 12:46 PM, David Vrabel wrote: > On 20/03/15 10:38, Vitaly Chernooky wrote: >> So I have finished my investigation and suggest to discuss the simple >> attaches patch. > > Looks ok to me. But this needs to go via the filesystem maintainers, > Cc'ing Linus on it. Just add Linus to cc? May be to continue mailing thread mentioned above will be better? WIth best regards, > You should explain the deadlock in more detail in > the commit message and mention that it fixes a regression and which > commit introduced the regression. Ok, > > Another solution would be to replace the file with a symlink to > /dev/xen/xenbus. > > David -- Vitaly Chernooky | Senior Developer - Product Engineering and Development GlobalLogic P +380.44.4929695 ext.1136 M +380.63.6011802 S cvv_2k www.globallogic.com http://www.globallogic.com/email_disclaimer.txt _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 11:39:11 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 11:39:11 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYvGh-0002Cn-FW; Fri, 20 Mar 2015 11:39:11 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYvGf-00026a-IL for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 11:39:09 +0000 Received: from [193.109.254.147] by server-9.bemta-14.messagelabs.com id C2/6A-17310-9D60C055; Fri, 20 Mar 2015 11:39:05 +0000 X-Env-Sender: vitalii.chernookyi@globallogic.com X-Msg-Ref: server-10.tower-27.messagelabs.com!1426851541!11803953!1 X-Originating-IP: [64.18.0.160] X-SpamReason: No, hits=0.8 required=7.0 tests=BODY_RANDOM_LONG, RCVD_BY_IP X-StarScan-Received: X-StarScan-Version: 6.13.6; banners=-,-,- X-VirusChecked: Checked Received: (qmail 27684 invoked from network); 20 Mar 2015 11:39:02 -0000 Received: from exprod5og118.obsmtp.com (HELO exprod5og118.obsmtp.com) (64.18.0.160) by server-10.tower-27.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 20 Mar 2015 11:39:02 -0000 Received: from mail-qc0-f171.google.com ([209.85.216.171]) (using TLSv1) by exprod5ob118.postini.com ([64.18.4.12]) with SMTP ID DSNKVQwG1B2kXe1biHrG3PhaO3iNAIEP1ngg@postini.com; Fri, 20 Mar 2015 04:39:02 PDT Received: by qcbkw5 with SMTP id kw5so90445147qcb.2 for ; Fri, 20 Mar 2015 04:39:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=globallogic.com; s=google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=Q1HGTelfyIKiQAUAtivYmMwuYABTNZtNS2OGmUS3+S4=; b=gvAX1wX4VrquFn8/b6qz72rz5eHykAPNEmPtYHf4riTbw9NAjGe1gAGypcH/Xb2WZj 0qeZFgfxyBptBeK8GKnHVADmEp6OB6+sZ/rkvJ/B6Rd0cTB2xn+rMTZw5XdNo6hRujYT sOBtPRuhoOKgRY7v0C+g0b4BzKtyDv33ER+ck= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=Q1HGTelfyIKiQAUAtivYmMwuYABTNZtNS2OGmUS3+S4=; b=PcMrKVT07bgUb+grgO+dBnAjZWpwdJuEC/1jA5QfK963lLQ7EwHw7IYP21hhmJnrCX fgHlO9ev8+9fd3HwIBmCT/HoX3fD5XVVtI3Bn0XUPitr9Ig6jEWyZ2Z2m9Do94gFp0SM 9XR4lrUAvQzs6VwqhlrczPT1Hp+gkua8xrH0cNS38vxWyyR44JuTtOEe8MrfGpuEFy8p m82GcJmdHR0O87xew2GLg4obZIkj1nj8kt97SpyCPWFBb3BuDWspRzNADGu0/Ujx/UOs WKgi6UWci7zD6tFe69WCJG0g5cteZ/BjDQpQO2deUB18K+UFOfKEGgNJYCVZSM+x4u9i 2/ug== X-Gm-Message-State: ALoCoQnR4qnU1Etv45pNo8z+MOA8HlyrnWQ+yjAIdSEWoseYnUqJa0zaLttpwNdUEG7Ww9EaxHNWbBxKJPpDvl5tyEsv9GVnuq2Y96xp7YwxmPT80l4kQ1Q9k9rwqBiQ6fi+xW8s5tyfWQxOoIVBcUi//YfNla7rgP75EQRNf+ErvmPAdhLxctk= X-Received: by 10.55.22.30 with SMTP id g30mr125191846qkh.54.1426851540231; Fri, 20 Mar 2015 04:39:00 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.55.22.30 with SMTP id g30mr125191833qkh.54.1426851540130; Fri, 20 Mar 2015 04:39:00 -0700 (PDT) Received: by 10.140.98.145 with HTTP; Fri, 20 Mar 2015 04:39:00 -0700 (PDT) In-Reply-To: <550BFA9E.8010102@citrix.com> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> <20150320040454.GZ2321@mail-itl> <550BFA9E.8010102@citrix.com> Date: Fri, 20 Mar 2015 13:39:00 +0200 Message-ID: From: Vitaly Chernooky To: David Vrabel Cc: Iurii Konovalenko , Ian Campbell , =?UTF-8?Q?Marek_Marczykowski=2DG=C3=B3recki?= , xen-devel , Embedded-pv-devel@lists.xenproject.org, Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org David, On Fri, Mar 20, 2015 at 12:46 PM, David Vrabel wrote: > On 20/03/15 10:38, Vitaly Chernooky wrote: >> So I have finished my investigation and suggest to discuss the simple >> attaches patch. > > Looks ok to me. But this needs to go via the filesystem maintainers, > Cc'ing Linus on it. Just add Linus to cc? May be to continue mailing thread mentioned above will be better? WIth best regards, > You should explain the deadlock in more detail in > the commit message and mention that it fixes a regression and which > commit introduced the regression. Ok, > > Another solution would be to replace the file with a symlink to > /dev/xen/xenbus. > > David -- Vitaly Chernooky | Senior Developer - Product Engineering and Development GlobalLogic P +380.44.4929695 ext.1136 M +380.63.6011802 S cvv_2k www.globallogic.com http://www.globallogic.com/email_disclaimer.txt _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 13:56:10 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 13:56:10 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYxPG-0005UI-NP; Fri, 20 Mar 2015 13:56:10 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYoBB-0007XC-LX for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 04:05:02 +0000 Received: from [85.158.137.68] by server-5.bemta-3.messagelabs.com id 0A/27-16504-C6C9B055; Fri, 20 Mar 2015 04:05:00 +0000 X-Env-Sender: marmarek@invisiblethingslab.com X-Msg-Ref: server-11.tower-31.messagelabs.com!1426824299!13897759!1 X-Originating-IP: [66.111.4.27] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTExLjQuMjcgPT4gODQ2Mw==\n X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 25295 invoked from network); 20 Mar 2015 04:05:00 -0000 Received: from out3-smtp.messagingengine.com (HELO out3-smtp.messagingengine.com) (66.111.4.27) by server-11.tower-31.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 20 Mar 2015 04:05:00 -0000 Received: from compute1.internal (compute1.nyi.internal [10.202.2.41]) by mailout.nyi.internal (Postfix) with ESMTP id E57FE204A5 for ; Fri, 20 Mar 2015 00:04:56 -0400 (EDT) Received: from frontend2 ([10.202.2.161]) by compute1.internal (MEProxy); Fri, 20 Mar 2015 00:04:59 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= invisiblethingslab.com; h=x-sasl-enc:date:from:to:cc:subject :message-id:references:mime-version:content-type:in-reply-to; s= mesmtp; bh=SVeUnpy76loIndP1P/GbhlGHeWI=; b=M1UMks9TgEd7iOjJUCAYj MOuylHc1soNLBMna8wwZQga9d5EV+4plN4QeZDJiK7l7DkNFEGqJ5GyGFHG7t8oR Pcn0shbFt0uSKxZEZG6fF2j9ev6lRVsQIRBoBJIHPMaAJrtvyclDehFgxncv1mVy SxA70/K07r42SrW8n9GOHk= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=x-sasl-enc:date:from:to:cc:subject :message-id:references:mime-version:content-type:in-reply-to; s= smtpout; bh=SVeUnpy76loIndP1P/GbhlGHeWI=; b=qVV8sk47QrU+NgHCtGjd 1aK/0dV6IJ+L1PDi9gu/8dgGGJYFrhhXzgV6/woI/TD4SNnnzysUIFfQUlB5sLEi B3q2G48KlT+7PnWf56R3WIPGrTbE5JsVrcHFVx10wYeWlZ33oI59cDHOrsd9MEBm Gb0AiJ5B0SSDx9+idBpPNlI= X-Sasl-enc: S6veFIjB/OeCOTxT/dEsf9Ran98EvWOQBU4LiGAnQNLS 1426824298 Received: from mail-itl (unknown [89.70.93.48]) by mail.messagingengine.com (Postfix) with ESMTPA id A1A006802D9; Fri, 20 Mar 2015 00:04:57 -0400 (EDT) Date: Fri, 20 Mar 2015 05:04:54 +0100 From: Marek =?utf-8?Q?Marczykowski-G=C3=B3recki?= To: Vitaly Chernooky Message-ID: <20150320040454.GZ2321@mail-itl> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-Mailman-Approved-At: Fri, 20 Mar 2015 13:56:09 +0000 Cc: Iurii Konovalenko , Ian Campbell , xen-devel , Embedded-pv-devel@lists.xenproject.org, David Vrabel , Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============2896327650233423278==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============2896327650233423278== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="U7PH6YjyT5379uVx" Content-Disposition: inline --U7PH6YjyT5379uVx Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Mar 19, 2015 at 03:10:49PM +0200, Vitaly Chernooky wrote: > David, >=20 > On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel > wrote: >=20 > > On 19/03/15 12:10, Iurii Konovalenko wrote: > > > Hi, guys! > > > > > > When I read, that I am not alone and that issue depends on kernel > > > version, I decided to continue investigation. > > > And I found why our threads locks on read/write operations. > > > On Linux kernel 3.14+ syscalls of file read and write changed a bit: > > > fdget() function was replaced by fdget_pos() - it is fdget() function > > > plus additional position mutex lock for files with FMODE_ATOMIC_POS > > > (files for inodes with S_IFREG flag set - regular nodes). As I thought > > > our xen files are not regular and nonseekable, I hoped this flag is > > > not set. But it is set. It is because our file system is created by > > > function simple_fill_super(), and inside it this flag is hardly set: > > > inode->i_mode =3D S_IFREG | files->mode; > > > So, as a fast hack I made a patch: just made copy of this function for > > > xen, which does not set this flag. It works for me. Could you please > > > check if it works for you. > > > > I still can't get this to deadlock, but why not clear FMODE_ATOMIC_POS > > in xenbus_file_open() ? > > >=20 > Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > results of bug. Iurii has fixed the root of issue but in suboptimal way. = So > we just need to have found optimal way. I can just confirm that: 1. (unsurprisingly) the bug is still present in 4.0-rc4 2. both proposed fixes are effective I'm not sure if removing S_IFREG completely is a good idea, I guess there will be much more side effects... What about another idea: xenbus_file_open uses nonseekable_open - this looks like a good place to clear FMODE_ATOMIC_POS if present? It doesn't make sense to get a lock for position on nonseekable file, right? --=20 Best Regards, Marek Marczykowski-G=C3=B3recki Invisible Things Lab A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? --U7PH6YjyT5379uVx Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJVC5xmAAoJENuP0xzK19csXZAH/0oPeVaIGttKOc9FGz8lfxZK 6QCRQgzdsXtwq8QKbZnkrQel4eWQ/nT7TJNa8nAT7sYDG+TvOFx0dXu0E8KBerR2 rwW0GtkXgLy9tX5nOFryEqG6A91W+ExeKfYkVe4qa3XXYX2poJgHGhhLGNO7qMrz K/Njd2m4tHPoGottA6idTGSw5zIrx2mZldDANx9luV78YWYidGI6JNI8EqxNQCt+ fwm+2Xke86oyapDfHTLGLILM7D0inZ0QeIa4+eyzwiXupi/JlfZ2aBPKICnt7PM+ 2gIMDpK+/JGOlp3/Dhl4Bw5K2mnVWZRQErmSSWxg1KUUxfLSWGOhvwWvqrhy8sU= =SDgX -----END PGP SIGNATURE----- --U7PH6YjyT5379uVx-- --===============2896327650233423278== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============2896327650233423278==-- From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 13:56:10 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 13:56:10 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYxPG-0005UI-NP; Fri, 20 Mar 2015 13:56:10 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYoBB-0007XC-LX for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 04:05:02 +0000 Received: from [85.158.137.68] by server-5.bemta-3.messagelabs.com id 0A/27-16504-C6C9B055; Fri, 20 Mar 2015 04:05:00 +0000 X-Env-Sender: marmarek@invisiblethingslab.com X-Msg-Ref: server-11.tower-31.messagelabs.com!1426824299!13897759!1 X-Originating-IP: [66.111.4.27] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTExLjQuMjcgPT4gODQ2Mw==\n X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 25295 invoked from network); 20 Mar 2015 04:05:00 -0000 Received: from out3-smtp.messagingengine.com (HELO out3-smtp.messagingengine.com) (66.111.4.27) by server-11.tower-31.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 20 Mar 2015 04:05:00 -0000 Received: from compute1.internal (compute1.nyi.internal [10.202.2.41]) by mailout.nyi.internal (Postfix) with ESMTP id E57FE204A5 for ; Fri, 20 Mar 2015 00:04:56 -0400 (EDT) Received: from frontend2 ([10.202.2.161]) by compute1.internal (MEProxy); Fri, 20 Mar 2015 00:04:59 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= invisiblethingslab.com; h=x-sasl-enc:date:from:to:cc:subject :message-id:references:mime-version:content-type:in-reply-to; s= mesmtp; bh=SVeUnpy76loIndP1P/GbhlGHeWI=; b=M1UMks9TgEd7iOjJUCAYj MOuylHc1soNLBMna8wwZQga9d5EV+4plN4QeZDJiK7l7DkNFEGqJ5GyGFHG7t8oR Pcn0shbFt0uSKxZEZG6fF2j9ev6lRVsQIRBoBJIHPMaAJrtvyclDehFgxncv1mVy SxA70/K07r42SrW8n9GOHk= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=x-sasl-enc:date:from:to:cc:subject :message-id:references:mime-version:content-type:in-reply-to; s= smtpout; bh=SVeUnpy76loIndP1P/GbhlGHeWI=; b=qVV8sk47QrU+NgHCtGjd 1aK/0dV6IJ+L1PDi9gu/8dgGGJYFrhhXzgV6/woI/TD4SNnnzysUIFfQUlB5sLEi B3q2G48KlT+7PnWf56R3WIPGrTbE5JsVrcHFVx10wYeWlZ33oI59cDHOrsd9MEBm Gb0AiJ5B0SSDx9+idBpPNlI= X-Sasl-enc: S6veFIjB/OeCOTxT/dEsf9Ran98EvWOQBU4LiGAnQNLS 1426824298 Received: from mail-itl (unknown [89.70.93.48]) by mail.messagingengine.com (Postfix) with ESMTPA id A1A006802D9; Fri, 20 Mar 2015 00:04:57 -0400 (EDT) Date: Fri, 20 Mar 2015 05:04:54 +0100 From: Marek =?utf-8?Q?Marczykowski-G=C3=B3recki?= To: Vitaly Chernooky Message-ID: <20150320040454.GZ2321@mail-itl> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-Mailman-Approved-At: Fri, 20 Mar 2015 13:56:09 +0000 Cc: Iurii Konovalenko , Ian Campbell , xen-devel , Embedded-pv-devel@lists.xenproject.org, David Vrabel , Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============2896327650233423278==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============2896327650233423278== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="U7PH6YjyT5379uVx" Content-Disposition: inline --U7PH6YjyT5379uVx Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Mar 19, 2015 at 03:10:49PM +0200, Vitaly Chernooky wrote: > David, >=20 > On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel > wrote: >=20 > > On 19/03/15 12:10, Iurii Konovalenko wrote: > > > Hi, guys! > > > > > > When I read, that I am not alone and that issue depends on kernel > > > version, I decided to continue investigation. > > > And I found why our threads locks on read/write operations. > > > On Linux kernel 3.14+ syscalls of file read and write changed a bit: > > > fdget() function was replaced by fdget_pos() - it is fdget() function > > > plus additional position mutex lock for files with FMODE_ATOMIC_POS > > > (files for inodes with S_IFREG flag set - regular nodes). As I thought > > > our xen files are not regular and nonseekable, I hoped this flag is > > > not set. But it is set. It is because our file system is created by > > > function simple_fill_super(), and inside it this flag is hardly set: > > > inode->i_mode =3D S_IFREG | files->mode; > > > So, as a fast hack I made a patch: just made copy of this function for > > > xen, which does not set this flag. It works for me. Could you please > > > check if it works for you. > > > > I still can't get this to deadlock, but why not clear FMODE_ATOMIC_POS > > in xenbus_file_open() ? > > >=20 > Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > results of bug. Iurii has fixed the root of issue but in suboptimal way. = So > we just need to have found optimal way. I can just confirm that: 1. (unsurprisingly) the bug is still present in 4.0-rc4 2. both proposed fixes are effective I'm not sure if removing S_IFREG completely is a good idea, I guess there will be much more side effects... What about another idea: xenbus_file_open uses nonseekable_open - this looks like a good place to clear FMODE_ATOMIC_POS if present? It doesn't make sense to get a lock for position on nonseekable file, right? --=20 Best Regards, Marek Marczykowski-G=C3=B3recki Invisible Things Lab A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? --U7PH6YjyT5379uVx Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJVC5xmAAoJENuP0xzK19csXZAH/0oPeVaIGttKOc9FGz8lfxZK 6QCRQgzdsXtwq8QKbZnkrQel4eWQ/nT7TJNa8nAT7sYDG+TvOFx0dXu0E8KBerR2 rwW0GtkXgLy9tX5nOFryEqG6A91W+ExeKfYkVe4qa3XXYX2poJgHGhhLGNO7qMrz K/Njd2m4tHPoGottA6idTGSw5zIrx2mZldDANx9luV78YWYidGI6JNI8EqxNQCt+ fwm+2Xke86oyapDfHTLGLILM7D0inZ0QeIa4+eyzwiXupi/JlfZ2aBPKICnt7PM+ 2gIMDpK+/JGOlp3/Dhl4Bw5K2mnVWZRQErmSSWxg1KUUxfLSWGOhvwWvqrhy8sU= =SDgX -----END PGP SIGNATURE----- --U7PH6YjyT5379uVx-- --===============2896327650233423278== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============2896327650233423278==-- From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 13:56:10 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 13:56:10 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYxPG-0005UX-P2; Fri, 20 Mar 2015 13:56:10 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYuNM-00089F-J3 for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 10:42:00 +0000 Received: from [85.158.139.211] by server-9.bemta-5.messagelabs.com id B7/E2-15508-779FB055; Fri, 20 Mar 2015 10:41:59 +0000 X-Env-Sender: marmarek@invisiblethingslab.com X-Msg-Ref: server-4.tower-206.messagelabs.com!1426848118!12122453!1 X-Originating-IP: [66.111.4.27] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTExLjQuMjcgPT4gODQ2Mw==\n X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 12402 invoked from network); 20 Mar 2015 10:41:59 -0000 Received: from out3-smtp.messagingengine.com (HELO out3-smtp.messagingengine.com) (66.111.4.27) by server-4.tower-206.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 20 Mar 2015 10:41:59 -0000 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.nyi.internal (Postfix) with ESMTP id 1347B208BC for ; Fri, 20 Mar 2015 06:41:56 -0400 (EDT) Received: from frontend2 ([10.202.2.161]) by compute4.internal (MEProxy); Fri, 20 Mar 2015 06:41:58 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= invisiblethingslab.com; h=x-sasl-enc:date:from:to:cc:subject :message-id:references:mime-version:content-type:in-reply-to; s= mesmtp; bh=+GW/2qqBkxdc4/6y+Bu5dIgrsPM=; b=ecv+r/YcSf1/MG6fWLpFh BXfbl7fNfKSWfogBrhCth2eyiJk0KrUOz1giYrZE3Uw6twnPAS1X0p67HN10BIvf QJOj4egMjIqiUTID+ny6UjUMGtbs57eMJcReOzgcAL49TQ84JzZqIxki6p8PmeuX ni86G7wN2A6MrJxH5Scr2Y= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=x-sasl-enc:date:from:to:cc:subject :message-id:references:mime-version:content-type:in-reply-to; s= smtpout; bh=+GW/2qqBkxdc4/6y+Bu5dIgrsPM=; b=P5z84Lw7MQ7ZJIARDSHA E0RDIoZXYzOfGOhIiG1CydlJT5Hns2PZEAfXPKXmZ2lnnOAWrGUArOfefepUCNSf 4r/+ygOD/vlIVrXPbC7TSL98i7Cti8nmfO8hrm+YtMNPJM2IHYZLEnxtSIDJHNjW 7/2Q0/anaijL9UFJcrI/eBs= X-Sasl-enc: ydnL3Av7/jGRn3TJBvwM5LY6x/bZttNjqdhWhMhIY/6R 1426848117 Received: from mail-itl (unknown [89.70.93.48]) by mail.messagingengine.com (Postfix) with ESMTPA id AA55A6801A3; Fri, 20 Mar 2015 06:41:56 -0400 (EDT) Date: Fri, 20 Mar 2015 11:41:52 +0100 From: Marek =?utf-8?Q?Marczykowski-G=C3=B3recki?= To: Vitaly Chernooky Message-ID: <20150320104152.GB2321@mail-itl> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> <20150320040454.GZ2321@mail-itl> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-Mailman-Approved-At: Fri, 20 Mar 2015 13:56:09 +0000 Cc: Iurii Konovalenko , Ian Campbell , xen-devel , Embedded-pv-devel@lists.xenproject.org, David Vrabel , Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1413379265714444575==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============1413379265714444575== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="VKLB3BcClAS4nArB" Content-Disposition: inline --VKLB3BcClAS4nArB Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Mar 20, 2015 at 12:08:48PM +0200, Vitaly Chernooky wrote: > On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3=B3recki < > marmarek@invisiblethingslab.com> wrote: >=20 > > On Thu, Mar 19, 2015 at 03:10:49PM +0200, Vitaly Chernooky wrote: > > > David, > > > > > > On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel > > > wrote: > > > > > > > On 19/03/15 12:10, Iurii Konovalenko wrote: > > > > > Hi, guys! > > > > > > > > > > When I read, that I am not alone and that issue depends on kernel > > > > > version, I decided to continue investigation. > > > > > And I found why our threads locks on read/write operations. > > > > > On Linux kernel 3.14+ syscalls of file read and write changed a b= it: > > > > > fdget() function was replaced by fdget_pos() - it is fdget() func= tion > > > > > plus additional position mutex lock for files with FMODE_ATOMIC_P= OS > > > > > (files for inodes with S_IFREG flag set - regular nodes). As I > > thought > > > > > our xen files are not regular and nonseekable, I hoped this flag = is > > > > > not set. But it is set. It is because our file system is created = by > > > > > function simple_fill_super(), and inside it this flag is hardly s= et: > > > > > inode->i_mode =3D S_IFREG | files->mode; > > > > > So, as a fast hack I made a patch: just made copy of this function > > for > > > > > xen, which does not set this flag. It works for me. Could you ple= ase > > > > > check if it works for you. > > > > > > > > I still can't get this to deadlock, but why not clear FMODE_ATOMIC_= POS > > > > in xenbus_file_open() ? > > > > > > > > > > Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > > > results of bug. Iurii has fixed the root of issue but in suboptimal w= ay. > > So > > > we just need to have found optimal way. > > > > I can just confirm that: > > 1. (unsurprisingly) the bug is still present in 4.0-rc4 > > 2. both proposed fixes are effective > > > > I'm not sure if removing S_IFREG completely is a good idea, I guess > > there will be much more side effects... > > What about another idea: xenbus_file_open uses nonseekable_open - this > > looks like a good place to clear FMODE_ATOMIC_POS if present? It > > doesn't make sense to get a lock for position on nonseekable file, > > right? > > >=20 > The Open Group Base Specifications Issue 7 IEEE Std 1003.1, 2013 Edition > requires from regular files to be seekable. But Linux kernel looks like > Linus has own opinion on it :((( Maybe the better idea would be to change filetype of xenbus (and others) to S_IFIFO or something like this (but keep the file type present, instead of removing it completely). Regarding the implementation, maybe simple_fill_super can be modified to not add S_IFREG if other file type is already present in files->mode? --=20 Best Regards, Marek Marczykowski-G=C3=B3recki Invisible Things Lab A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? --VKLB3BcClAS4nArB Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJVC/lwAAoJENuP0xzK19csH54H/jSO6xm6pY+bGiwJ9vnbh72p yd2oDsIqJrO6r25ym6rLvn8mmzCIDuutvdXCFJtT5nFERYbhvjVsdxGCLtXVh4KR /FOcGLyOE6KCdRYGvQft62CO7zWQuf6/iZGUqgGfJoJ9yHAbQ9N951dqKSh9AXUU Gslck1rHI+XmebOwampe9qCqehU2JvaPNzX1oYA3bhNmQ0Ril8OxGzJgqw6V1cof dnbAumDgA0BA1YSdUPCTiQF0vxDkRnsJm6Re3SF+olJrnJZyQVTtFMZyr/18F5Rg B19q7RoLtgUUq0tHKjEl24fym2Or+hSEaoTWHPNOqtVWhvi0bVHvVCPR7rowGQ4= =EZAN -----END PGP SIGNATURE----- --VKLB3BcClAS4nArB-- --===============1413379265714444575== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============1413379265714444575==-- From embedded-pv-devel-bounces@lists.xenproject.org Fri Mar 20 13:56:10 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Fri, 20 Mar 2015 13:56:10 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYxPG-0005UX-P2; Fri, 20 Mar 2015 13:56:10 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YYuNM-00089F-J3 for Embedded-pv-devel@lists.xenproject.org; Fri, 20 Mar 2015 10:42:00 +0000 Received: from [85.158.139.211] by server-9.bemta-5.messagelabs.com id B7/E2-15508-779FB055; Fri, 20 Mar 2015 10:41:59 +0000 X-Env-Sender: marmarek@invisiblethingslab.com X-Msg-Ref: server-4.tower-206.messagelabs.com!1426848118!12122453!1 X-Originating-IP: [66.111.4.27] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTExLjQuMjcgPT4gODQ2Mw==\n X-StarScan-Received: X-StarScan-Version: 6.13.4; banners=-,-,- X-VirusChecked: Checked Received: (qmail 12402 invoked from network); 20 Mar 2015 10:41:59 -0000 Received: from out3-smtp.messagingengine.com (HELO out3-smtp.messagingengine.com) (66.111.4.27) by server-4.tower-206.messagelabs.com with DHE-RSA-AES256-SHA encrypted SMTP; 20 Mar 2015 10:41:59 -0000 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.nyi.internal (Postfix) with ESMTP id 1347B208BC for ; Fri, 20 Mar 2015 06:41:56 -0400 (EDT) Received: from frontend2 ([10.202.2.161]) by compute4.internal (MEProxy); Fri, 20 Mar 2015 06:41:58 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= invisiblethingslab.com; h=x-sasl-enc:date:from:to:cc:subject :message-id:references:mime-version:content-type:in-reply-to; s= mesmtp; bh=+GW/2qqBkxdc4/6y+Bu5dIgrsPM=; b=ecv+r/YcSf1/MG6fWLpFh BXfbl7fNfKSWfogBrhCth2eyiJk0KrUOz1giYrZE3Uw6twnPAS1X0p67HN10BIvf QJOj4egMjIqiUTID+ny6UjUMGtbs57eMJcReOzgcAL49TQ84JzZqIxki6p8PmeuX ni86G7wN2A6MrJxH5Scr2Y= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=x-sasl-enc:date:from:to:cc:subject :message-id:references:mime-version:content-type:in-reply-to; s= smtpout; bh=+GW/2qqBkxdc4/6y+Bu5dIgrsPM=; b=P5z84Lw7MQ7ZJIARDSHA E0RDIoZXYzOfGOhIiG1CydlJT5Hns2PZEAfXPKXmZ2lnnOAWrGUArOfefepUCNSf 4r/+ygOD/vlIVrXPbC7TSL98i7Cti8nmfO8hrm+YtMNPJM2IHYZLEnxtSIDJHNjW 7/2Q0/anaijL9UFJcrI/eBs= X-Sasl-enc: ydnL3Av7/jGRn3TJBvwM5LY6x/bZttNjqdhWhMhIY/6R 1426848117 Received: from mail-itl (unknown [89.70.93.48]) by mail.messagingengine.com (Postfix) with ESMTPA id AA55A6801A3; Fri, 20 Mar 2015 06:41:56 -0400 (EDT) Date: Fri, 20 Mar 2015 11:41:52 +0100 From: Marek =?utf-8?Q?Marczykowski-G=C3=B3recki?= To: Vitaly Chernooky Message-ID: <20150320104152.GB2321@mail-itl> References: <20150319011911.GA29029@mail-itl> <1426761512.610.18.camel@citrix.com> <550AC883.40008@citrix.com> <20150320040454.GZ2321@mail-itl> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-Mailman-Approved-At: Fri, 20 Mar 2015 13:56:09 +0000 Cc: Iurii Konovalenko , Ian Campbell , xen-devel , Embedded-pv-devel@lists.xenproject.org, David Vrabel , Boris Ostrovsky Subject: Re: [Embedded-pv-devel] [Xen-devel] Deadlock in /proc/xen/xenbus watch+read on 3.17+ (maybe earlier) X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1413379265714444575==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============1413379265714444575== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="VKLB3BcClAS4nArB" Content-Disposition: inline --VKLB3BcClAS4nArB Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Mar 20, 2015 at 12:08:48PM +0200, Vitaly Chernooky wrote: > On Fri, Mar 20, 2015 at 6:04 AM, Marek Marczykowski-G=C3=B3recki < > marmarek@invisiblethingslab.com> wrote: >=20 > > On Thu, Mar 19, 2015 at 03:10:49PM +0200, Vitaly Chernooky wrote: > > > David, > > > > > > On Thu, Mar 19, 2015 at 3:00 PM, David Vrabel > > > wrote: > > > > > > > On 19/03/15 12:10, Iurii Konovalenko wrote: > > > > > Hi, guys! > > > > > > > > > > When I read, that I am not alone and that issue depends on kernel > > > > > version, I decided to continue investigation. > > > > > And I found why our threads locks on read/write operations. > > > > > On Linux kernel 3.14+ syscalls of file read and write changed a b= it: > > > > > fdget() function was replaced by fdget_pos() - it is fdget() func= tion > > > > > plus additional position mutex lock for files with FMODE_ATOMIC_P= OS > > > > > (files for inodes with S_IFREG flag set - regular nodes). As I > > thought > > > > > our xen files are not regular and nonseekable, I hoped this flag = is > > > > > not set. But it is set. It is because our file system is created = by > > > > > function simple_fill_super(), and inside it this flag is hardly s= et: > > > > > inode->i_mode =3D S_IFREG | files->mode; > > > > > So, as a fast hack I made a patch: just made copy of this function > > for > > > > > xen, which does not set this flag. It works for me. Could you ple= ase > > > > > check if it works for you. > > > > > > > > I still can't get this to deadlock, but why not clear FMODE_ATOMIC_= POS > > > > in xenbus_file_open() ? > > > > > > > > > > Because it is not the root of issue. FMODE_ATOMIC_POS is just one of > > > results of bug. Iurii has fixed the root of issue but in suboptimal w= ay. > > So > > > we just need to have found optimal way. > > > > I can just confirm that: > > 1. (unsurprisingly) the bug is still present in 4.0-rc4 > > 2. both proposed fixes are effective > > > > I'm not sure if removing S_IFREG completely is a good idea, I guess > > there will be much more side effects... > > What about another idea: xenbus_file_open uses nonseekable_open - this > > looks like a good place to clear FMODE_ATOMIC_POS if present? It > > doesn't make sense to get a lock for position on nonseekable file, > > right? > > >=20 > The Open Group Base Specifications Issue 7 IEEE Std 1003.1, 2013 Edition > requires from regular files to be seekable. But Linux kernel looks like > Linus has own opinion on it :((( Maybe the better idea would be to change filetype of xenbus (and others) to S_IFIFO or something like this (but keep the file type present, instead of removing it completely). Regarding the implementation, maybe simple_fill_super can be modified to not add S_IFREG if other file type is already present in files->mode? --=20 Best Regards, Marek Marczykowski-G=C3=B3recki Invisible Things Lab A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? --VKLB3BcClAS4nArB Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJVC/lwAAoJENuP0xzK19csH54H/jSO6xm6pY+bGiwJ9vnbh72p yd2oDsIqJrO6r25ym6rLvn8mmzCIDuutvdXCFJtT5nFERYbhvjVsdxGCLtXVh4KR /FOcGLyOE6KCdRYGvQft62CO7zWQuf6/iZGUqgGfJoJ9yHAbQ9N951dqKSh9AXUU Gslck1rHI+XmebOwampe9qCqehU2JvaPNzX1oYA3bhNmQ0Ril8OxGzJgqw6V1cof dnbAumDgA0BA1YSdUPCTiQF0vxDkRnsJm6Re3SF+olJrnJZyQVTtFMZyr/18F5Rg B19q7RoLtgUUq0tHKjEl24fym2Or+hSEaoTWHPNOqtVWhvi0bVHvVCPR7rowGQ4= =EZAN -----END PGP SIGNATURE----- --VKLB3BcClAS4nArB-- --===============1413379265714444575== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============1413379265714444575==-- From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 24 10:59:04 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 24 Mar 2015 10:59:04 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YaMY4-0006Ew-4Q; Tue, 24 Mar 2015 10:59:04 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YaMY2-0006A7-Ro; Tue, 24 Mar 2015 10:59:02 +0000 Received: from [193.109.254.147] by server-11.bemta-14.messagelabs.com id A8/48-32337-67341155; Tue, 24 Mar 2015 10:59:02 +0000 X-Env-Sender: lars.kurth.xen@gmail.com X-Msg-Ref: server-13.tower-27.messagelabs.com!1427194737!12664761!1 X-Originating-IP: [74.125.82.50] X-SpamReason: No, hits=0.0 required=7.0 tests=HTML_MESSAGE X-StarScan-Received: X-StarScan-Version: 6.13.6; banners=-,-,- X-VirusChecked: Checked Received: (qmail 13452 invoked from network); 24 Mar 2015 10:58:57 -0000 Received: from mail-wg0-f50.google.com (HELO mail-wg0-f50.google.com) (74.125.82.50) by server-13.tower-27.messagelabs.com with RC4-SHA encrypted SMTP; 24 Mar 2015 10:58:57 -0000 Received: by wgbcc7 with SMTP id cc7so167887362wgb.0; Tue, 24 Mar 2015 03:58:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:content-type:subject:message-id:date:to:mime-version; bh=f8yXY+FSYPUATf6LgvzK7QWSMQZA8bGylUxkCezZMOo=; b=kEjPthmrbtOvz/ayM80igTNkJ81NGlGAsDeEmoBGdaMqA5ZlUOfm/xYJ2ch2Mw5hux 4wD4mxzY80t1OPhfzhPocSAF0C5E0nqR591eg/rbCZ0+HlEnGPHR8fX3RADJXsPY2yRN YgPvQQS43VcgQ6giZwedinzYQGz0CBsIftLqvZ8BzNQyl1zBgIFRjrMGwyxk5sEJo3eF pB5g//Wm93Amvz/ZQDnRzmo38W2EjgU6P9zInY63usGo9OYGUUl9LvDV7UoaAGK0M6T8 05xz3b4k7/qAUaU/siBSsPRPm+JB1jLMGWQib+1/YzwzuxAy72qZ+tCcBCvq6rqWaGi3 yr/Q== X-Received: by 10.194.88.131 with SMTP id bg3mr6755276wjb.119.1427194737421; Tue, 24 Mar 2015 03:58:57 -0700 (PDT) Received: from [192.168.0.12] (97e5522d.skybroadband.com. [151.229.82.45]) by mx.google.com with ESMTPSA id e2sm5523649wjy.46.2015.03.24.03.58.56 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 24 Mar 2015 03:58:56 -0700 (PDT) From: Lars Kurth Message-Id: <0A96B756-8A67-4E1E-9A13-39238BF378C3@gmail.com> Date: Tue, 24 Mar 2015 10:58:55 +0000 To: xen-devel , xen-api@lists.xenproject.org, Win-pv-devel@lists.xenproject.org, embedded-pv-devel@lists.xenproject.org, mirageos-devel@xenproject.org Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) X-Mailer: Apple Mail (2.2070.6) Subject: [Embedded-pv-devel] March Advisory Board Meeting Minutes X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============0772717509675996280==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============0772717509675996280== Content-Type: multipart/alternative; boundary="Apple-Mail=_11348BEA-F535-490A-B658-13DC5C385749" --Apple-Mail=_11348BEA-F535-490A-B658-13DC5C385749 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii See http://wiki.xenproject.org/wiki/AB_Meeting/March_2015_Minutes = = --Apple-Mail=_11348BEA-F535-490A-B658-13DC5C385749 Content-Transfer-Encoding: 7bit Content-Type: text/html; charset=us-ascii See http://wiki.xenproject.org/wiki/AB_Meeting/March_2015_Minutes --Apple-Mail=_11348BEA-F535-490A-B658-13DC5C385749-- --===============0772717509675996280== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============0772717509675996280==-- From embedded-pv-devel-bounces@lists.xenproject.org Tue Mar 24 10:59:04 2015 Return-path: Envelope-to: archives@lists.xenproject.org Delivery-date: Tue, 24 Mar 2015 10:59:04 +0000 Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YaMY4-0006Ew-4Q; Tue, 24 Mar 2015 10:59:04 +0000 Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YaMY2-0006A7-Ro; Tue, 24 Mar 2015 10:59:02 +0000 Received: from [193.109.254.147] by server-11.bemta-14.messagelabs.com id A8/48-32337-67341155; Tue, 24 Mar 2015 10:59:02 +0000 X-Env-Sender: lars.kurth.xen@gmail.com X-Msg-Ref: server-13.tower-27.messagelabs.com!1427194737!12664761!1 X-Originating-IP: [74.125.82.50] X-SpamReason: No, hits=0.0 required=7.0 tests=HTML_MESSAGE X-StarScan-Received: X-StarScan-Version: 6.13.6; banners=-,-,- X-VirusChecked: Checked Received: (qmail 13452 invoked from network); 24 Mar 2015 10:58:57 -0000 Received: from mail-wg0-f50.google.com (HELO mail-wg0-f50.google.com) (74.125.82.50) by server-13.tower-27.messagelabs.com with RC4-SHA encrypted SMTP; 24 Mar 2015 10:58:57 -0000 Received: by wgbcc7 with SMTP id cc7so167887362wgb.0; Tue, 24 Mar 2015 03:58:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:content-type:subject:message-id:date:to:mime-version; bh=f8yXY+FSYPUATf6LgvzK7QWSMQZA8bGylUxkCezZMOo=; b=kEjPthmrbtOvz/ayM80igTNkJ81NGlGAsDeEmoBGdaMqA5ZlUOfm/xYJ2ch2Mw5hux 4wD4mxzY80t1OPhfzhPocSAF0C5E0nqR591eg/rbCZ0+HlEnGPHR8fX3RADJXsPY2yRN YgPvQQS43VcgQ6giZwedinzYQGz0CBsIftLqvZ8BzNQyl1zBgIFRjrMGwyxk5sEJo3eF pB5g//Wm93Amvz/ZQDnRzmo38W2EjgU6P9zInY63usGo9OYGUUl9LvDV7UoaAGK0M6T8 05xz3b4k7/qAUaU/siBSsPRPm+JB1jLMGWQib+1/YzwzuxAy72qZ+tCcBCvq6rqWaGi3 yr/Q== X-Received: by 10.194.88.131 with SMTP id bg3mr6755276wjb.119.1427194737421; Tue, 24 Mar 2015 03:58:57 -0700 (PDT) Received: from [192.168.0.12] (97e5522d.skybroadband.com. [151.229.82.45]) by mx.google.com with ESMTPSA id e2sm5523649wjy.46.2015.03.24.03.58.56 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 24 Mar 2015 03:58:56 -0700 (PDT) From: Lars Kurth Message-Id: <0A96B756-8A67-4E1E-9A13-39238BF378C3@gmail.com> Date: Tue, 24 Mar 2015 10:58:55 +0000 To: xen-devel , xen-api@lists.xenproject.org, Win-pv-devel@lists.xenproject.org, embedded-pv-devel@lists.xenproject.org, mirageos-devel@xenproject.org Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) X-Mailer: Apple Mail (2.2070.6) Subject: [Embedded-pv-devel] March Advisory Board Meeting Minutes X-BeenThere: embedded-pv-devel@lists.xenproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============0772717509675996280==" Sender: embedded-pv-devel-bounces@lists.xenproject.org Errors-To: embedded-pv-devel-bounces@lists.xenproject.org --===============0772717509675996280== Content-Type: multipart/alternative; boundary="Apple-Mail=_11348BEA-F535-490A-B658-13DC5C385749" --Apple-Mail=_11348BEA-F535-490A-B658-13DC5C385749 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii See http://wiki.xenproject.org/wiki/AB_Meeting/March_2015_Minutes = = --Apple-Mail=_11348BEA-F535-490A-B658-13DC5C385749 Content-Transfer-Encoding: 7bit Content-Type: text/html; charset=us-ascii See http://wiki.xenproject.org/wiki/AB_Meeting/March_2015_Minutes --Apple-Mail=_11348BEA-F535-490A-B658-13DC5C385749-- --===============0772717509675996280== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Embedded-pv-devel mailing list Embedded-pv-devel@lists.xenproject.org http://lists.xenproject.org/cgi-bin/mailman/listinfo/embedded-pv-devel --===============0772717509675996280==--