From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH V5 1/1] bpf: control events stored in PERF_EVENT_ARRAY
 maps trace data output when perf sampling
Date: Wed, 21 Oct 2015 15:49:51 +0200
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Cc: Alexei Starovoitov <ast@plumgrid.com>,
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To: "Wangnan (F)" <wangnan0@huawei.com>
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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?