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Message-ID: <1345463210.23018.36.camel@twins>
Subject: Re: lockdep trace from posix timers
From: Peter Zijlstra <peterz@infradead.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Dave Jones <davej@redhat.com>, Linux Kernel <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>, rostedt <rostedt@goodmis.org>,
        dhowells <dhowells@redhat.com>, Al Viro <viro@zeniv.linux.org.uk>
Date: Mon, 20 Aug 2012 13:46:50 +0200
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On Mon, 2012-08-20 at 13:44 +0200, Peter Zijlstra wrote:
> > I'm not at all sure how that relates to needing task_lock() in the
> > keyctl stuff. 

Ah, is it used to serialize against exit_mm() so that the !->mm check
will suffice to avoid queuing works past exit_task_work() ?