[PATCH 0/2] KVM: arm64: PMU: Preserve vPMC registers properly on migration

[Reiji Watanabe]

Hi Marc,

On Sun, Mar 12, 2023 at 8:04 AM Marc Zyngier <maz at kernel.org> wrote:
>
> On Thu, 02 Mar 2023 05:50:31 +0000,
> Reiji Watanabe <reijiw at google.com> wrote:
> >
> > The series fixes two problems in preserving vPMU counter (vPMC)
> > registers (PMCCNTR_EL0/PMEVCNTR<n>_EL0) during migration.
> >
> > One of the problems is that KVM may not return the current values
> > of the vPMC registers for KVM_GET_ONE_REG.
> >
> > The other one might cause KVM to reset the vPMC registers on the
> > first KVM_RUN on the destination. This is because userspace might
> > save PMCR_EL0 with PMCR_EL0.{C,P} bits set on the source, and
> > restore it on the destination.
>
> This looks good to me. Can you please add the relevant Fixes: tags and
> a Cc: to stable? With that, that'd be a candidate for -rc3, I think.

Thank you for the review!

I posted v2, which addressed the comments above, and the comment
for the patch-2 (remove the line break).

Thank you,
Reiji



>
> Thanks,
>
>         M.
>
> --
> Without deviation from the norm, progress is not possible.