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Date: Thu, 8 May 2014 01:51:44 +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>
Subject: Re: perf_fuzzer crash on pentium 4
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On Wed, May 07, 2014 at 05:17:22PM -0400, Vince Weaver wrote:
> On Wed, 7 May 2014, Cyrill Gorcunov wrote:
> 
> > > I thought I was running with PeterZ's latest patch that was supposed to 
> > > avoid the corruption.  Hmmm.  Let me reboot and try a few more things.
> > 
> > Thanks! Please ping me if find something new.
> 
> It turns out to be my fault, I was running with an incomplete version of 
> PeterZ's patch.  We need to get the fix into the kernel as apparently I 
> fail at manually applying patches across multiple machines.
> 
> So to summarize, with PeterZ's fix the various memory corruption crashes 
> in the p4 code no longer happen.

Good. Thanks a lot, Vince!

> 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?