Re: [PATCH 0/2] KVM: PPC: support kvm selftests

[Sean Christopherson <seanjc@google.com>]

On Thu, Mar 16, 2023, Michael Ellerman wrote:
> Nicholas Piggin <npiggin@gmail.com> writes:
> > Hi,
> >
> > This series adds initial KVM selftests support for powerpc
> > (64-bit, BookS).
> 
> Awesome.
>  
> > It spans 3 maintainers but it does not really
> > affect arch/powerpc, and it is well contained in selftests
> > code, just touches some makefiles and a tiny bit headers so
> > conflicts should be unlikely and trivial.
> >
> > I guess Paolo is the best point to merge these, if no comments
> > or objections?
> 
> Yeah. If it helps:
> 
> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)

What is the long term plan for KVM PPC maintenance?  I was under the impression
that KVM PPC was trending toward "bug fixes only", but the addition of selftests
support suggests otherwise.

I ask primarily because routing KVM PPC patches through the PPC tree is going to
be problematic if KVM PPC sees signficiant development.  The current situation is
ok because the volume of patches is low and KVM PPC isn't trying to drive anything
substantial into common KVM code, but if that changes... 

My other concern is that for selftests specifically, us KVM folks are taking on
more maintenance burden by supporting PPC.  AFAIK, none of the people that focus
on KVM selftests in any meaningful capacity have access to PPC hardware, let alone
know enough about the architecture to make intelligent code changes.

Don't get me wrong, I'm very much in favor of more testing, I just don't want KVM
to get left holding the bag.