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Date: Fri, 2 May 2014 18:22:34 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Vince Weaver <vincent.weaver@maine.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>, 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 Fri, May 02, 2014 at 12:22:30PM -0400, Vince Weaver wrote:
>=20
> I'll try the patch next.
>=20
> Meanwhile, can polling on a closed event cause problems with the referenc=
e=20
> count?
>=20
> In my various failure traces there's always been a poll() active at the=
=20
> time of crash, and I added some trace_printk()s and it looks like poll is=
=20
> at least attempting to poll on the closed file descriptor that's causing=
=20
> us problems.

In principle the vfs file refcounting should be responsible for that.
But I'll go over it in a bit.

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