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

[Eric Farman <farman@linux.ibm.com>]

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.

Eric