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From:   Vince Weaver <vincent.weaver@maine.edu>
Date:   Fri, 4 May 2018 13:00:27 -0400 (EDT)
To:     Josh Poimboeuf <jpoimboe@redhat.com>
cc:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>, linux-kernel@vger.kernel.org,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Andy Lutomirski <luto@kernel.org>
Subject: Re: perf: fuzzer causes stack going in wrong direction warnings
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On Fri, 4 May 2018, Josh Poimboeuf wrote:

> Also, any tips for reproducing this locally?  I cloned the perf fuzzer
> github.  Is it as simple as just "make" and "./run_tests.sh"?

run_tests only runs the perf_event regressiong tests.

To run the fuzzer, enter the "fuzzer" directory and either run
	"./fast_repro98.sh"
which will run the fuzzer repeatedly, or you can instead just run
	./perf_fuzzer
but that sometimes eventually errors out if it manages to get stuck in a 
signal storm.

While running on haswell and skylake machines the WARNINGs trigger fairly 
quickly (within minutes usually).

You might also encounter a handful of other known kernel warnings which 
I've reported in the past and usually just ignore.

Vince