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

Ping: [PATCH] x86: mark hypercall argument regs clobbering for intended fall-through


  • To: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
  • From: Jan Beulich <jbeulich@xxxxxxxx>
  • Date: Wed, 30 Jun 2021 08:47:11 +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-SenderADCheck; bh=lLwd1wlSUaqk94eww1pmuux6R3MK0OD5v99tOaIyXNs=; b=Kivi4BT2WlA+GbVWr+d3whTObIKLA7lqezP04nerpT3qsL2ME7yxmSE5zhd+mopFo44xyE5rvyL9Cu+lcWv/wKnB668Sn3F9tS4fFnmdEfi81XLQAwnM0kxyDY/r3NQh6jiSkkF+cWy78HBoleRXUKSbWS68+syeMMiglICjTxyihqD8vQaY+AE0VXcloSc1bhI8OVEBrUd5FtqhfPsoqX9i5i6KhEEJOnqE4LrzTLyHXNbkntprE4UZybhV5/V3F4iIYga2sPe3UvP6z5rE+f3WgmY9+SzbiCEKMnK23Jqv3VQ/wlxnXZ3CEzx4At7+g+0pEHKCi3aiEpxApBz2MA==
  • Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Hg1TASnbXwEDOeP7c5K7z8A6G2/kjfjBhCG3wyPLtWBkn55KEAUfy+f13Cf5JnSNxZRmgXmRgt+SfQmtJXRwVrrDH/imD/PxYfcfwK4/sbA1jmmkz/+DMf6qe3FO4Hd/e/VpnbCYFJ/pA4Lz/AeETv302ngPgjt8U3js7/pTmeDbv5OV9CviDuuGq1v22wyiqaGNuXWByOlf6wLRxjSRDlrIM/N7nDeYWzhPkCbMG77bg6gMmpQFTpPPfWASIcxQmt8u67q5N34k3ka/X7nUwRSrS5Z6M9iF9T23wP3/Xfxf7FZAa/oJtMl8YTW377f5+i6gkO2Eh+5NJnwp972XdA==
  • Authentication-results: lists.xenproject.org; dkim=none (message not signed) header.d=none;lists.xenproject.org; dmarc=none action=none header.from=suse.com;
  • Cc: Wei Liu <wl@xxxxxxx>, Roger Pau Monné <roger.pau@xxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxxx>
  • Delivery-date: Wed, 30 Jun 2021 06:47:19 +0000
  • List-id: Xen developer discussion <xen-devel.lists.xenproject.org>

On 09.06.2021 14:49, Andrew Cooper wrote:
> On 09/06/2021 11:34, Jan Beulich wrote:
>> The CIDs below are all for the PV side of things, but also take care of
>> the HVM side.
>>
>> Coverity-ID: 1485896, 1485901, 1485906, 1485910, 1485911, 
>> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
>> ---
>> Let's see whether Coverity actually understands the (relatively) new
>> pseudo-keyword.
> 
> This is exceedingly disappointing.  Coverity used to have the only
> sensible rule for not causing spurious fallthrough warnings, but this
> has apparently regressed.
> 
> Coverity works on the AST, so ought to be after GCC has interpreted
> __attribute__((__fallthrough__)) if applicable.
> 
> However, I doubt it will work in the fallback case, because #define
> fallthrough looks dubious.  To trigger the older logic, the /*
> fallthrough */ comment needs to be the final thing before the next case
> label, and it isn't with the added semicolon.
> 
> Given that this pseudo-keyword is restricted to the SMMU driver for now,
> we don't actually know if Coverity likes it or not.

My reply from the 9th had no further reaction, so let me ask more
directly: Besides leaving the Coverity issues open, what alternatives
do you see? IOW I'm missing from your reply any indication what it
would rework of the patch you want me to do, if any. Or if none, what
it is that stands in the way of getting this change in.

Jan




 


Rackspace

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