Re: [PATCH v2 4/5] perf/amd/ibs: Avoid calling perf_allow_kernel() from the IBS NMI handler

[Ravi Bangoria]

Hi Michael,

> By evaluating the privileges at the event-init moment and using cached
> value later, couldn't it lead to the cached value being obsolete at
> some point? E.g. a setuid program later dropping the privileges but
> still being able to read physical addresses?

Yes, but wouldn't the same concern apply to all other call sites of
perf_allow_kernel() ?

Thanks,
Ravi