Re: [PATCH] KVM: s390: fix cc for successful PQAP

Anthony Krowiak
2023-12-08T14:21:17Z

On 12/8/23 6:24 AM, Eric Farman wrote:
> On Fri, 2023-12-08 at 11:31 +0100, Janosch Frank wrote:
>> On 12/1/23 19:16, Eric Farman wrote:
>>> The various errors that are possible when processing a PQAP
>>> instruction (the absence of a driver hook, an error FROM that
>>> hook), all correctly set the PSW condition code to 3. But if
>>> that processing works successfully, CC0 needs to be set to
>>> convey that everything was fine.
>>>
>>> Fix the check so that the guest can examine the condition code
>>> to determine whether GPR1 has meaningful data.
>>>
>> Hey Eric, I have yet to see this produce a fail in my AP KVM unit
>> tests.
>> If you find some spare time I'd like to discuss how I can extend my
>> test
>> so that I can see the fail before it's fixed.
>>
> Hi Janosch, absolutely. I had poked around kvm-unit-tests before I sent
> this up to see if I could adapt something to show this scenario, but
> came up empty and didn't want to go too far down that rabbit hole
> creating something from scratch. I'll ping you offline to find a time
> to talk.

If this is recreateable, I'd like to know how. I don't see any code path
that would cause this result.

>
> Eric
>