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

Re: [PATCH v2 01/12] xen/trace: Don't over-read trace objects


  • To: Dario Faggioli <dfaggioli@xxxxxxxx>
  • From: Jan Beulich <jbeulich@xxxxxxxx>
  • Date: Mon, 27 Sep 2021 09:51:37 +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; bh=dPxg+uspY3zJhaK/lOcD+C16I8PeoXPTSu3CuLLjkB0=; b=Al6XWkUpBR3KpXit5SMVm2oivQUbuQweF8XYoEnsnyR/KUu4gay/T3IK//tyXUkdA0jnZpDOgQ5I14zk/wMu7fMKQBZWDVpX+/KqLT/09HbZG+B5/6LBd6iueZDjPiRHENZkzEVZgkGSULQGG1zCQvWO3yckw1bVq3d8ORyDPp/829M4V6QBQl04D7veIRsN2YJN/fUywW9goeE41Ra2eFcMUM9CK/6P/Lba7WUCdJltcxMu61MYXXOMctGEqcctpNyNrX8pf72UPifwFUD0aisz4TASOujYjuxIzA91ejODG4C68prgza012wL+dubVUmIUl1dRIqSR07XV4dqKEw==
  • Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=itJbM019zuBCp+3ZVwvzsIduLdMxS4DQIC3NpSj1mSuf6Zwk+2h9z4KVkwYS8SCXxsQHDboV8cCFNf9CIegIKdmVEMeARnRxmisn15/pryUSofG+mzYjyQnMF8Oa2FYkpyGqqhNrIjG6wcI7UsTNQ9Qf4jDJsbcWZdLdxPR/VLyfOU+VuJrRlmBEwxQUJf1DIFXbAZvFfYbfANaOpGX6L5Am66GfKVNgnL8oaRy01wxeTgZ7ZBTw4nl4aIU7mlGz3atB7nLM8O6G/JEhAeBrh/wopnaZWdXl0dY2GQk5imwi5hBebfrvYZOVncVM1ZPGPz8gfEziezZEF8JSGMpNJA==
  • 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: "julien@xxxxxxx" <julien@xxxxxxx>, "George.Dunlap@xxxxxxxxxxxxx" <George.Dunlap@xxxxxxxxxxxxx>, "sstabellini@xxxxxxxxxx" <sstabellini@xxxxxxxxxx>, "iwj@xxxxxxxxxxxxxx" <iwj@xxxxxxxxxxxxxx>, "wl@xxxxxxx" <wl@xxxxxxx>, "mengxu@xxxxxxxxxxxxx" <mengxu@xxxxxxxxxxxxx>, "andrew.cooper3@xxxxxxxxxx" <andrew.cooper3@xxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxxx>
  • Delivery-date: Mon, 27 Sep 2021 07:51:44 +0000
  • List-id: Xen developer discussion <xen-devel.lists.xenproject.org>

On 24.09.2021 16:51, Dario Faggioli wrote:
> On Mon, 2021-09-20 at 18:25 +0100, Andrew Cooper wrote:
> 
>> There is one buggy race record, TRC_RTDS_BUDGET_BURN.  As it must
>> remain
>> __packed (as cur_budget is misaligned), change bool has_extratime to
>> uint32_t
>> to compensate.
>>
> Mmm... maybe my understanding of data alignment inside structs is a bit
> lacking, but what the actual issue here, and what would we need to do
> to fix it (where, by fix, I mean us being able to get rid of the
> `__packed`)?
> 
> If rearranging fields is not enough, we can think about making
> priority_level and has_extratime smaller, or even combining them in
> just one field and decode the information in xentrace.

I guess Andrew has tried to avoid re-arranging field order so that
the consumer side doesn't need to also change.

Jan




 


Rackspace

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