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Date: Tue, 15 May 2012 08:31:36 -0700
From: Tejun Heo <tj@kernel.org>
To: Dave Jones <davej@redhat.com>, Peter Zijlstra <peterz@infradead.org>,
        Hugh Dickins <hughd@google.com>, Ingo Molnar <mingo@kernel.org>,
        Ingo Molnar <mingo@redhat.com>, Stephen Boyd <sboyd@codeaurora.org>,
        Yong Zhang <yong.zhang0@gmail.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] lockdep: fix oops in processing workqueue
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On Tue, May 15, 2012 at 11:29:52AM -0400, Dave Jones wrote:
> On Tue, May 15, 2012 at 08:10:48AM -0700, Tejun Heo wrote:
>  > >From 4d82a1debbffec129cc387aafa8f40b7bbab3297 Mon Sep 17 00:00:00 2001
>  > From: Peter Zijlstra <peterz@infradead.org>
>  > Date: Tue, 15 May 2012 08:06:19 -0700
>  > 
>  > Under memory load, on x86_64, with lockdep enabled, the workqueue's
>  > process_one_work() has been seen to oops in __lock_acquire(), barfing
>  > on a 0xffffffff00000000 pointer in the lockdep_map's class_cache[].
> 
> can you elaborate what 'memory load' means here ?
> I'm curious if I can add something to my fuzzing tool to shake out bugs like this.

I think Hugh knows and can explain this much better than I do.  Hugh?

Thanks.

-- 
tejun