Re: [PATCH] perf/core: fix the bug in the event multiplexing

[Oliver Upton]

On Wed, Aug 09, 2023 at 09:48:29AM +0100, Marc Zyngier wrote:

[...]

> Another question is how the same thing is handled on x86? Maybe they
> don't suffer from this problem thanks to specific architectural
> features, but it'd be good to find out, as this may guide the
> implementation in a different way.

I'm pretty sure the bug here is arm64 specific. x86 (at least on intel)
fetches the guest PMU context from the perf driver w/ irqs disabled
immediately before entering the guest (see atomic_switch_perf_msrs()).

-- 
Thanks,
Oliver