From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: lockdep: strange %s#5 lock name
Date: Thu, 13 Feb 2014 22:32:53 +0100
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To: Tejun Heo <tj@kernel.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>, Tommi Rantala <tt.rantala@gmail.com>, Ingo Molnar <mingo@redhat.com>, LKML <linux-kernel@vger.kernel.org>, Dave Jones <davej@redhat.com>, trinity@vger.kernel.org

On Thu, Feb 13, 2014 at 04:26:45PM -0500, Tejun Heo wrote:
> > It seems to me that when the second time alloc_workqueue() is called
> > from the same code path, it would have two locks with the same key, but
> > not the same &wq->name, which doesn't meet lockdep's assumption.
> 
> Dang...  I reverted the previous patch for now.  Peter, does this
> approach sound good to you?

Whatever works I suppose; like Li said; a little ugly but not sure we
can do better.