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Date: Tue, 29 Mar 2011 21:53:29 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Steven Rostedt <rostedt@goodmis.org>
cc: LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>
Subject: Re: [RFC][PATCH] lockdep: Print a nice description of an irq locking
 issue
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On Tue, 29 Mar 2011, Steven Rostedt wrote:
>     other info that might help us debug this:
>     
>     Chain exists of:
>       &rq->lock --> lockA --> lockC
>     
>      Possible interrupt unsafe locking scenario:
>     
>            CPU0                    CPU1
>            ----                    ----
>       lock(lockC);
>                                    local_irq_disable();
>                                    lock(&rq->lock);
>                                    lock(lockA);
>       <Interrupt>
>         lock(&rq->lock)
>     
>      *** DEADLOCK ***

Cool stuff. I always have to twist my brain around those splats as
well :)

Thanks,

	tglx