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Date: Tue, 6 Jan 2015 12:34:20 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Chris Wilson <chris@chris-wilson.co.uk>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
        Daniel Vetter <daniel.vetter@ffwll.ch>
Subject: Re: [PATCH] mutex: Always clear owner field upon mutex_unlock()
Message-ID: <20150106113420.GR29390@twins.programming.kicks-ass.net>
References: <1420540175-30204-1-git-send-email-chris@chris-wilson.co.uk>
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On Tue, Jan 06, 2015 at 10:29:35AM +0000, Chris Wilson wrote:
> Currently if DEBUG_MUTEXES is enabled, the mutex->owner field is only
> cleared iff debug_locks is active. This exposes a race to other users of
> the field where the mutex->owner may be still set to a stale value,
> potentially upsetting mutex_spin_on_owner() among others.


Thanks