From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mark Brown <broonie@opensource.wolfsonmicro.com>
Subject: Re: Deadlock scenario in regulator core
Date: Wed, 23 Mar 2011 00:01:01 +0000
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To: Steven Rostedt <rostedt@goodmis.org>
Cc: David Collins <collinsd@codeaurora.org>, Liam Girdwood <lrg@slimlogic.co.uk>, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@elte.hu>

On Tue, Mar 22, 2011 at 07:19:58PM -0400, Steven Rostedt wrote:

> Looks to me that the mutex_lock() in _notifier_call_chain needs to be a
> mutex_lock_nested().

> The "_nested()" versions are when you have the same type of mutex taken
> but belonging to two different instances. Like you have here:

What's a mutex type?  I have to say this is the first time I've heard of
mutex types and the documentation in mutex.c and mutex-design.txt isn't
precisely verbose on what mutex_lock_nested() is for or how one would
pick subclass.