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From: Alexander Shishkin <alexander.shishkin@linux.intel.com>
To: Vince Weaver <vincent.weaver@maine.edu>, linux-kernel@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>
Subject: Re: perf: WARNING: kernel/events/core.c:4893 perf_mmap_close
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Date: Tue, 09 Aug 2016 08:15:17 +0300
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Vince Weaver <vincent.weaver@maine.edu> writes:

> Hello
>
> running the perf_fuzzer on Haswell, this is a new warning I don't think 
> I've seen before.
>
> It works out to be this code here:
>
>                 /* this has to be the last one */
>                 rb_free_aux(rb);
>                 WARN_ON_ONCE(atomic_read(&rb->aux_refcount));
>
>                 mutex_unlock(&event->mmap_mutex);

Awesome, I'll have a look. Can you tell it it was messing around with
intel_bts driver from the fuzzer log?

Thanks,
--
Alex