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Message-ID: <1345446957.23018.14.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 09:15:57 +0200
In-Reply-To: <20120817151447.GA7918@redhat.com>
References: <20120724203613.GA9637@redhat.com>
	 <1345140478.29668.54.camel@twins> <20120817151447.GA7918@redhat.com>
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On Fri, 2012-08-17 at 17:14 +0200, Oleg Nesterov wrote:
> I still think that task_work_add() should synhronize with exit_task_work()
> itself and fail if necessary. But I wasn't able to convince Al ;)

I'm not at all sure how that relates to needing task_lock() in the
keyctl stuff.

Also, can't task_work use llist stuff? That would also avoid using
->pi_lock.