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Message-ID: <425ba458-3eba-4742-930d-1248be2c2cd3@linux.ibm.com>
Date:   Thu, 26 Oct 2023 14:18:39 -0400
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Subject: Re: [PATCH v2 3/3] s390/vfio-ap: improve reaction to response code 07
 from PQAP(AQIC) command
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To:     Matthew Rosato <mjrosato@linux.ibm.com>,
        linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
Cc:     jjherne@linux.ibm.com, pasic@linux.ibm.com,
        borntraeger@linux.ibm.com, frankja@linux.ibm.com,
        imbrenda@linux.ibm.com, david@redhat.com
References: <20231018133829.147226-1-akrowiak@linux.ibm.com>
 <20231018133829.147226-4-akrowiak@linux.ibm.com>
 <0bed3d29-7fb1-d56d-5f12-e2010ae7d97f@linux.ibm.com>
From:   Tony Krowiak <akrowiak@linux.ibm.com>
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On 10/26/23 10:15, Matthew Rosato wrote:
> On 10/18/23 9:38 AM, Tony Krowiak wrote:
>> Let's improve the vfio_ap driver's reaction to reception of response code
>> 07 from the PQAP(AQIC) command when enabling interrupts on behalf of a
>> guest:
>>
>> * Unregister the guest's ISC before the pages containing the notification
>>    indicator bytes are unpinned.
>>
>> * Capture the return code from the kvm_s390_gisc_unregister function and
>>    log a DBF warning if it fails.
>>
>> Suggested-by: Matthew Rosato <mjrosato@linux.ibm.com>
>> Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
> 
> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
> 
> I went back-and-forth on whether this should be a stable/fixes candidate but I think no...  I happened to notice it while reviewing other code, I'm not aware that it's ever created a visible issue, and it's on a pretty immediate error path.  If anyone thinks it should be a stable candidate I have no objection but in that case would suggest to break the patch up to separate the new WARN from the fix.

Nothing has ever been reported and is probably very unlikely to be 
reported; so, I agree it should not be a stable/fixes candidate.

> 
> 
>