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Date: Mon, 8 Jan 2018 18:30:05 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>
Subject: Re: perf: perf_fuzzer quickly locks up on 4.15-rc7
Message-ID: <20180108173005.lkglqrixb2ota6g2@gmail.com>
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* Vince Weaver <vincent.weaver@maine.edu> wrote:

> Hello
> 
> Was trying out current git (4.15-rc7) and the perf_fuzzer very quickly 
> will lock up my Haswell test machine so solidly that I don't get any debug 
> info, even with a serial console.

That's pretty concerning ...

> I'll try enabling various debug options to see if I can get a more useful 
> bug report.

Note that the page table isolation (PTI) feature has a number of effects on perf 
and on NMI handlers, so one of the things to try would be to disable PTI.

Thanks,

	Ingo