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Date:   Thu, 26 Oct 2023 10:15:11 -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:     Tony Krowiak <akrowiak@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>
From:   Matthew Rosato <mjrosato@linux.ibm.com>
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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.