[PATCH v2 1/2] KVM: arm64: PMU: Fix GET_ONE_REG for vPMC regs to return the current value

Oliver Upton oliver.upton at linux.dev
Mon Mar 13 12:02:54 PDT 2023


On Sun, 12 Mar 2023 20:32:08 -0700, Reiji Watanabe wrote:
> Have KVM_GET_ONE_REG for vPMU counter (vPMC) registers (PMCCNTR_EL0
> and PMEVCNTR<n>_EL0) return the sum of the register value in the sysreg
> file and the current perf event counter value.
> 
> Values of vPMC registers are saved in sysreg files on certain occasions.
> These saved values don't represent the current values of the vPMC
> registers if the perf events for the vPMCs count events after the save.
> The current values of those registers are the sum of the sysreg file
> value and the current perf event counter value.  But, when userspace
> reads those registers (using KVM_GET_ONE_REG), KVM returns the sysreg
> file value to userspace (not the sum value).
> 
> [...]

Applied to kvmarm/fixes, thanks!

[1/2] KVM: arm64: PMU: Fix GET_ONE_REG for vPMC regs to return the current value
      https://git.kernel.org/kvmarm/kvmarm/c/9228b26194d1

--
Best,
Oliver



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