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Date: Thu, 1 May 2014 12:26:02 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>, Ingo Molnar <mingo@kernel.org>,
        linux-kernel@vger.kernel.org, Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [perf] more perf_fuzzer memory corruption
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On Thu, May 01, 2014 at 12:51:33AM +0200, Thomas Gleixner wrote:
> And that's the issue which puzzles us. Let's look at what we expect:
> 
> Now the trace shows a different story:
> 
>      perf_fuzzer-4387  [001]  1802.628659: sys_enter:            NR 298 (69bb58, 0, ffffffff, 12, 0, 0)

That's a per-cpu event (.pid = -1, .cpu = 12), they don't get inherited,
so the only thing keeping it alive is the fd the child got. So
exit_files() killing this thing makes perfect sense.

Onwards to find another funny.