Re: [PATCH] KVM: x86/pmu: Add '.exclude_hv = 1' for guest perf_event

From: Paolo Bonzini
Date: Wed Aug 12 2020 - 09:04:53 EST


On 12/08/20 14:56, Xu, Like wrote:
>
> My proposal is to define:
> the "hypervisor privilege levels" events in the KVM/x86 context as
> all the host kernel events plus /dev/kvm user space events.

What are "/dev/kvm user space events"? In any case, this patch should
be included only in the series that adds exclude_hv support in arch/x86.

Paolo

> If we add ".exclude_hv = 1" in the pmc_reprogram_counter(),
> do you see any side effect to cover the above usages?
>
> The fact that exclude_hv has never been used in x86 does help
> the generic perf code to handle permission checks in a more concise way.