Re: [PATCH V5 1/1] bpf: control events stored in PERF_EVENT_ARRAY maps trace data output when perf sampling

From: Peter Zijlstra
Date: Wed Oct 21 2015 - 09:50:08 EST


On Wed, Oct 21, 2015 at 09:42:12PM +0800, Wangnan (F) wrote:
> How can an eBPF program access a !local event:
>
> when creating perf event array we don't care which perf event
> is for which CPU, so perf program can access any perf event in
> that array.

So what is stopping the eBPF thing from calling perf_event_read_local()
on a !local event and triggering a kernel splat?

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