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Date: Tue, 17 Feb 2015 13:53:42 +0100
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>, LKML <linux-kernel@vger.kernel.org>,
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        Thomas Gleixner <tglx@linutronix.de>, Carsten Emde <C.Emde@osadl.org>,
        John Kacur <jkacur@redhat.com>, Clark Williams <williams@redhat.com>
Subject: Re: 3.14.23-rt20 - aio: fix rcu garbage collection might_sleep()
 splat
Message-ID: <20150217125342.GJ26177@linutronix.de>
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* Mike Galbraith | 2014-11-02 08:31:28 [+0100]:

>(not pretty)

You do the RCU thingy and replace locking. Is this required after the
patch I've sent in "Re: [RFC PATCH V2] rt/aio: fix rcu garbage
collection might_sleep() splat"? From a quick browse I've seen that
ffs_epfile_aio_write() invokes kiocb_set_cancel_fn(, ffs_aio_cancel) and
the function does hold a sleeping lock.

Sebastian