On Sat, Aug 28, 2021, Peter Zijlstra wrote:
> On Fri, Aug 27, 2021 at 05:35:46PM -0700, Sean Christopherson wrote:
> > diff --git a/kernel/events/core.c b/kernel/events/core.c
> > index 464917096e73..2126f6327321 100644
> > --- a/kernel/events/core.c
> > +++ b/kernel/events/core.c
> > @@ -6491,14 +
On Fri, Aug 27, 2021 at 05:35:46PM -0700, Sean Christopherson wrote:
> diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
> index 2d510ad750ed..6b0405e578c1 100644
> --- a/include/linux/perf_event.h
> +++ b/include/linux/perf_event.h
> @@ -1237,6 +1237,14 @@ extern void perf_even
Protect perf_guest_cbs with READ_ONCE/WRITE_ONCE to ensure it's not
reloaded between a !NULL check and a dereference, and wait for all
readers via syncrhonize_rcu() to prevent use-after-free, e.g. if the
callbacks are being unregistered during module unload. Because the
callbacks are global, it's
