From: Vince Weaver <vincent.weaver@maine.edu>
Date: Tue, 9 Jan 2018 10:24:55 -0500 (EST)
To: Peter Zijlstra <peterz@infradead.org>
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
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On Tue, 9 Jan 2018, Peter Zijlstra wrote:

> > I'll try your patch and see if it makes a difference.
> 
> I suspect not, it shouldn't be PTI specific.

yes, applying your patch didn't help, still locks up on the Haswell 
machine.

Is there any debugging I could turn on that would help?  I tried KASAN 
but it didn't help.  I think I have the regular lockdep stuff enabled.

alt-sysrq doesn't work either (or at least, the version using BREAK over 
the serial console doesn't, I can maybe try hooking up a keyboard/display 
to see if that helps).

Vince