Date: Thu, 11 Jan 2018 10:13:53 +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: <20180111091353.GW6176@hirez.programming.kicks-ass.net>
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On Tue, Jan 09, 2018 at 08:44:23AM -0500, Vince Weaver wrote:
> On Tue, 9 Jan 2018, Peter Zijlstra wrote:
> 
> > So remind me again, how are you running that fuzzer? I'm running
> > ./fast_repro99.sh as root.
> 
> I'm running ./fast_repro98.sh on a regular haswell machine with paranoid 
> set to "0".

I'm seeing things like:

Cannot open /sys/kernel/tracing/kprobe_events

this is likely caused by me not having anything mounted there. Rostedt
provided the magic incantation to make that work, I'll go try now.

At least I seem to have cured all lockdep splats.. of course, the moment
I hit send on this someone bad is bound to happen.