Re: [PATCH v2 3/3] s390/vfio-ap: improve reaction to response code 07 from PQAP(AQIC) command

From: Matthew Rosato
Date: Thu Oct 26 2023 - 10:15:23 EST


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@xxxxxxxxxxxxx>
> Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>

Reviewed-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>

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.