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Date: Thu, 8 May 2014 01:54:30 +0400
From: Cyrill Gorcunov <gorcunov@gmail.com>
To: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org, Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>, Don Zickus <dzickus@redhat.com>
Subject: Re: perf_fuzzer crash on pentium 4
Message-ID: <20140507215430.GH8607@moon>
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On Thu, May 08, 2014 at 01:51:44AM +0400, Cyrill Gorcunov wrote:
> 
> > When fuzzing on the p4 *other* things do happen.
> > 	* at least two warnings pop up almost instantly
> > 	* eventually the machine will crash in an endless NMI storm
> > 	* also I managed to get the machine wedged with an unkillable
> > 	  process, sort of like the known problem PeterZ has.
> > 
> > The NMI issue is probably the only one that is p4 related, and I do get 
> > the NMI warnings on other machines too, it's just the p4 is the only one 
> > where it brings down the machine.
> 
> Vince, could you please provde more details on that? Is it possible
> to somehow log which events were used by perf?

There were a bug in p4 pmu Don (CC'ed) fixed not that long ago but I fear
not all corner cases might be covered yet.