Date: Thu, 11 Jan 2018 21:57:00 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Vince Weaver <vincent.weaver@maine.edu>
Cc: Ingo Molnar <mingo@kernel.org>, linux-kernel@vger.kernel.org,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: perf: perf_fuzzer quickly locks up on 4.15-rc7
Message-ID: <20180111205700.GG3397@worktop>
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On Thu, Jan 11, 2018 at 03:40:44PM -0500, Vince Weaver wrote:
> On Thu, 11 Jan 2018, Vince Weaver wrote:
> 
> > Not sure if this info helps, but if I make perf_fuzzer *not* create AUX 
> > mmap() buffers, I'm unable to reproduce the hangs both on core2 and 
> > haswell.
> 
> Confirmed, I can crash the system without the fuzzer, just by doing
> 
> 	perf record --per-thread -e intel_bts// /bin/ls
> 
> on my haswell system.

It makes my IVB very ill, starts spewing RCU stall warnings, but is
otherwise very unresponsive.

Awesome... I'll prod at it when my brain works again.