linux-kernel - Re: [PATCH 1/1] iommu/vt-d: Don't set then immediately clear in prq_event

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Fri, 19 Mar 2021 09:07:54 +0800
From:   Lu Baolu <baolu.lu@...ux.intel.com>
To:     Joerg Roedel <joro@...tes.org>
Cc:     baolu.lu@...ux.intel.com, Will Deacon <will@...nel.org>,
        ashok.raj@...el.com, kevin.tian@...el.com, jacob.jun.pan@...el.com,
        yi.l.liu@...el.com, sanjay.k.kumar@...el.com,
        iommu@...ts.linux-foundation.org, linux-kernel@...r.kernel.org,
        Jacob Pan <jacob.jun.pan@...ux.intel.com>
Subject: Re: [PATCH 1/1] iommu/vt-d: Don't set then immediately clear in
 prq_event_thread()

Hi Joerg,

On 3/18/21 6:10 PM, Joerg Roedel wrote:
> Hi Baolu,
> 
> On Tue, Mar 09, 2021 at 08:46:41AM +0800, Lu Baolu wrote:
>> The private data field of a page group response descriptor is set then
>> immediately cleared in prq_event_thread(). Fix this by moving clearing
>> code up.
>>
>> Fixes: 5b438f4ba315d ("iommu/vt-d: Support page request in scalable mode")
>> Cc: Jacob Pan <jacob.jun.pan@...ux.intel.com>
>> Reviewed-by: Liu Yi L <yi.l.liu@...el.com>
>> Signed-off-by: Lu Baolu <baolu.lu@...ux.intel.com>
> 
> Does this fix an actual bug? If so, please state it in the commit

It will cause real problem according to the VT-d spec. I haven't got a
chance run this on a real hardware yet. I'll add a commit message to
explain why this will cause problem.

> message and also fix the subject line to state what is set/cleared.
> 

Sure!

> Thanks,
> 
> 	Joerg
> 

Best regards,
baolu