[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Need help to debug Arm SMMU issue seen on guests with passthrough devices


  • To: Ayan Kumar Halder <ayan.kumar.halder@xxxxxxxxxx>
  • From: Jan Beulich <jbeulich@xxxxxxxx>
  • Date: Thu, 21 Apr 2022 13:47:39 +0200
  • Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=suse.com; dmarc=pass action=none header.from=suse.com; dkim=pass header.d=suse.com; arc=none
  • Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=ldsrMJ1vOYDMITcqJ1do5pRntxT9UX/xi9Q6RLrswm0=; b=Em5WyOVNAXYOJlhnaRHPiXW+ELBUn9x+uwKM1DLUz0oVqfLSrHpxU12Xl4dTqHLZEUMDyYFu/c+mdgr6SyJkwC6acefV2U48MaP48a9xuoF6bb3BOXyaCd0ztiir+/LYNoQi7QgeCIJn4WzH3oc/ogolMOFaq+4Gel/Bq8mK0lyqRmz2SC7A2wbCAWSG/avqXrXkp4/EDJaxzjviT/IOMxY7lkwCTVcpxFp31AN6kZDXVyRPubzevZWFmiM3iigupvlLZixysgcf7co16y4+5tuZuhcL4FS1W9KAaUWuDWr1qpD5UOrwL4XQ8G/Gia1uFYUu9EuaNk6Vh9AXgFnCwg==
  • Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=HLHSacRFvSQ/BLHoTEUZH7C8ziY0kMZCJrVWu2sW/UQvbbNTOgUBI9SdL1JpAMaQBG9EWAyCJLQWLGYKjTiZ0pt9FsaXBDX+zwopp1XJXq+Wegrv+eT/N2vNGz6R8LfexlW37BriTG0+7AMiebXwlL+55rXY2mB8EY+Fafct/HOEvlOR9HcjaS4hsOOG477kegNdzHxJrYF4o1uDPTRPpAEwURWIV49YL12oK6lsrvztkoj5hWv+gPzBQmjNVA/9ehbwC/W8iRSFcXBS9hXmzuv0yqR0vwEL3knGIZtPfcbdE8jhbQflNA5qMZsOtigJfoPa6e8FG6Cn59tRzYqucg==
  • Authentication-results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=suse.com;
  • Cc: "xen-devel@xxxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxxx>, Rahul Singh <rahul.singh@xxxxxxx>, Bertrand Marquis <Bertrand.Marquis@xxxxxxx>, Stefano Stabellini <sstabellini@xxxxxxxxxx>, Julien Grall <julien@xxxxxxx>, Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>
  • Delivery-date: Thu, 21 Apr 2022 11:48:06 +0000
  • List-id: Xen developer discussion <xen-devel.lists.xenproject.org>

On 21.04.2022 13:12, Ayan Kumar Halder wrote:
> Hi Arm/SMMU experts,
> 
> Scenario :- I am trying to assign a device (eg mmc) to a guest which 
> uses smmu. I start the guest using "xl create -c ...". It works fine for 
> the first time. I am able to access the device.
> 
> Now, when I destroy the guest and create again, I see this issue
> 
> (XEN) smmu: /axi/smmu@fd800000:         GFSR 0x00000002, GFSYNR0 
> 0x00000000, GFSYNR1 0x00000871, GFSYNR2 0x00000000
> 
> 0x871 is the stream id used by mmc.
> 
> We are using SMMU-500. So from the Arm SMMU v2 specs, it is 
> "Unidentified stream fault" for stream id "0x871".

I have no clue what any of this means. I wonder how I ended up on your
To: list. I'd like to ask everyone to drop me from the recipients list
in their replies.

Jan

> This issue is seen regardless we use 'mmu-masters' or 'iommus' property 
> in xen device tree.
> 
> I can confirm that this issue was not seen in xen-4.14.3. It is seen in 
> our (Xilinx's) latest release ie xen-4.16.1.
> 
> I am using our downstream fork of Xen. I can't readily use the upstream 
> as we use lot of EEMI codebase.
> 
> 
> Can someone try to see if this issue exists in the latest upstream Xen ?
> 
> Any pointers on how to debug this further ?
> 
> Kind regards,
> 
> Ayan
> 
> 
> 
> 
> 




 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.