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Date: Wed, 18 Jun 2014 22:11:18 -0400
From: Chris Mason <clm@fb.com>
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To: Marc Dionne <marc.c.dionne@gmail.com>, Waiman Long <waiman.long@hp.com>
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Subject: Re: Lockups with btrfs on 3.16-rc1 - bisected
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On 06/18/2014 10:03 PM, Marc Dionne wrote:
> On Wed, Jun 18, 2014 at 8:41 PM, Marc Dionne <marc.c.dionne@gmail.com> wrote:
>> On Wed, Jun 18, 2014 at 8:08 PM, Waiman Long <waiman.long@hp.com> wrote:
>>> On 06/18/2014 08:03 PM, Marc Dionne wrote:
> 
> And for an additional data point, just removing those
> CONFIG_DEBUG_LOCK_ALLOC ifdefs looks like it's sufficient to prevent
> the symptoms when lockdep is not enabled.

Ok, somehow we've added a lock inversion here that wasn't here before.
Thanks for confirming, I'll nail it down.

-chris