Date: Fri, 25 May 2012 15:01:41 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Alan Cox <alan@linux.intel.com>, Ming Lei <ming.lei@canonical.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-kernel@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>
Subject: Re: [PATCH] tty: tty_mutex: fix lockdep warning in
 tty_lock_pair(v1)
Message-ID: <20120525150141.7a099aa3@pyramind.ukuu.org.uk>
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On Fri, 25 May 2012 15:52:02 +0200
Peter Zijlstra <peterz@infradead.org> wrote:

> On Fri, 2012-05-25 at 14:47 +0100, Alan Cox wrote:
> > > Having looked at the source I still don't see how it could possibly
> > > work,.. So the problem with tty_release() -> tty_ldisc_release() is
> > > that tty_ldisc_release() does an unlock/lock of tty.
> > 
> > Yes it should do the pair, see the patch I posted restructing it, and
> > the second one restructing it right.
> 
> http://marc.info/?l=linux-kernel&m=133794355529930
> 
> That one? To what tree does one apply that? Because the tty_lock_pair()
> in Linus is still missing a lockdep annotation afaict.

It applies on top of the other patches being tested in the thread on the
lockdep warning.

Alan
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