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

[Xu, Like]

On 2020/8/12 21:04, Paolo Bonzini wrote:
> 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.
The exclude_kernel events from the QEMU or whoever else has opened /dev/kvm.

Do you see any (patches) gap if we map
the exclude_host events into exclude_hv events naturally ?

Thanks,
Like Xu
> 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.