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Date: Thu, 29 May 2014 17:07:05 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Sasha Levin <sasha.levin@oracle.com>
Cc: Ingo Molnar <mingo@kernel.org>, acme@ghostprotocols.net,
        LKML <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>, Dave Jones <davej@redhat.com>
Subject: Re: perf: use after free in perf_remove_from_context
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On Thu, May 29, 2014 at 10:47:09AM -0400, Sasha Levin wrote:
> It doesn't work out well because we later lock a mutex in sync_child_event().
> 

Urgh, right you are. I'll go stare at it more. It shouldn't have
mattered, because the mutex we take just before should ensure existence,
but.. you know.. :-)