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Date: Fri, 19 Jul 2013 15:36:44 -0400
From: Rik van Riel <riel@redhat.com>
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To: Peter Zijlstra <peterz@infradead.org>
CC: Waiman Long <Waiman.Long@hp.com>, Davidlohr Bueso <davidlohr.bueso@hp.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        David Howells <dhowells@redhat.com>, Ingo Molnar <mingo@kernel.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mutex: Fix mutex_can_spin_on_owner
References: <20130719183101.GA20909@twins.programming.kicks-ass.net>
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On 07/19/2013 02:31 PM, Peter Zijlstra wrote:
>
> mutex_can_spin_on_owner() is broken in that it would allow the compiler
> to load lock->owner twice, seeing a pointer first time and a MULL
> pointer the second time.
>
> Signed-off-by: Peter Zijlstra <peterz@infradead.org>

Reviewed-by: Rik van Riel <riel@redhat.com>

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