Re: [PATCH 4.19 49/58] KVM: x86/pmu: Use AMD64_RAW_EVENT_MASK for PERF_TYPE_RAW

Pavel Machek
2022-02-22T15:37:53Z

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Hi!

> [ Upstream commit 710c476514313c74045c41c0571bb5178fd16e3d ]
>
> AMD's event select is 3 nybbles, with the high nybble in bits 35:32 of
> a PerfEvtSeln MSR. Don't mask off the high nybble when configuring a
> RAW perf event.

Ok, but this depends on b8bfee "KVM: x86/pmu: Don't truncate the
PerfEvtSeln MSR when creating a perf event", and that is backported to
5.10 but not 4.19... so we don't need this, either, right...?

Best regards,
Pavel

> +++ b/arch/x86/kvm/pmu.c
> @@ -171,7 +171,7 @@ void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel)
> }
>
> if (type == PERF_TYPE_RAW)
> - config = eventsel & X86_RAW_EVENT_MASK;
> + config = eventsel & AMD64_RAW_EVENT_MASK;
>
> pmc_reprogram_counter(pmc, type, config,
> !(eventsel & ARCH_PERFMON_EVENTSEL_USR),

--
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