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Date: Tue, 5 Jan 2016 13:17:27 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>, Arnaldo Carvalho de Melo <acme@kernel.org>,
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        Alexander Potapenko <glider@google.com>,
        Eric Dumazet <edumazet@google.com>,
        Sasha Levin <sasha.levin@oracle.com>
Subject: Re: use-after-free in __perf_install_in_context
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On Thu, Dec 31, 2015 at 06:15:41PM +0100, Dmitry Vyukov wrote:
> On Thu, Dec 17, 2015 at 3:43 PM, Peter Zijlstra <peterz@infradead.org> wrote:
> > On Thu, Dec 17, 2015 at 03:35:32PM +0100, Dmitry Vyukov wrote:
> >> In short, I did not see use-after-frees but perf_event_open fuzzing
> >> started hanging VMs very frequently, so testing is inconclusive.
> >
> > Right, I'll get back to staring at that one.
> >
> > Running your test case on bare metal got my machine reproducably stuck
> > but in a different place than you've reported.
> >
> > Takes a while too, so far no luck in explaining/debugging it. All my
> > added debug code remains silent :/
> >
> > I'll go think up more ..
> 
> Hi Peter,
> 
> Any progress with this?
> I can't continue to test perf subsytem, as it reliably hangs my machines.

Holidays got in the way, I'll continue asap when I've cleared some of
the easy mail backlog from the past two weeks.