Re: [PATCH v3 2/3] s390/vfio-ap: set status response code to 06 on gisc registration failure

[Tony Krowiak]

On 10/27/23 07:19, Halil Pasic wrote:
> On Thu, 26 Oct 2023 14:32:44 -0400
> Tony Krowiak <akrowiak@xxxxxxxxxxxxx> wrote:
>
> > Since this scenario is very unlikely to happen and there is no status
> > response code to indicate an invalid ISC value, let's set the
>
> Again invalid ISC won't happen except for hypervisor messes up.

Again, that is one of the checks performed by the kvm_s390_gisc_register
function; however, I get your point and will remove reference in the 
comment.

> > response code to 06 indicating 'Invalid address of AP-queue notification
> > byte'. While this is not entirely accurate, it is better than indicating
> > that the ZONE/GISA designation is invalid which is something the guest
> > can do nothing about since those values are set by the hypervisor.
>
> And more importantly AP_RESPONSE_INVALID_GISA is not valid for G2 in
> the given scenario, since G2 is not trying to set up interrupts on behalf
> of the G3 with a G3 GISA, but G2 is trying to set up interrupts for
> itself. And then AP_RESPONSE_INVALID_GISA is architecturally simply not
> a valid RC!

Got it.

> > Signed-off-by: Anthony Krowiak <akrowiak@xxxxxxxxxxxxx>
> > Suggested-by: Halil Pasic <pasic@xxxxxxxxxxxxx>
>
> Except for the explanation in the commit message, the patch is good. It
> is up to you if you want to fix the commit message or not.

I'll fix the commit message.

> Reviewed-by: Halil Pasic <pasic@xxxxxxxxxxxxx>