On Sun, 12 Mar 2023 20:32:34 -0700, Reiji Watanabe wrote:
> Presently, when a guest writes 1 to PMCR_EL0.{C,P}, which is WO/RAZ,
> KVM saves the register value, including these bits.
> When userspace reads the register using KVM_GET_ONE_REG, KVM returns
> the saved register value as it is (the saved value might have these
> bits set). This could result in userspace setting these bits on the
> destination during migration. Consequently, KVM may end up resetting
> the vPMU counter registers (PMCCNTR_EL0 and/or PMEVCNTR<n>_EL0) to
> zero on the first KVM_RUN after migration.
>
> [...]
Applied to kvmarm/fixes, thanks!
[2/2] KVM: arm64: PMU: Don't save PMCR_EL0.{C,P} for the vCPU
https://git.kernel.org/kvmarm/kvmarm/c/f6da81f650fa
--
Best,
Oliver
