From mboxrd@z Thu Jan  1 00:00:00 1970
From: peter@hurleysoftware.com (Peter Hurley)
Date: Thu, 27 Dec 2012 08:03:24 -0500
Subject: [REGRESSION][3.8.-rc1][ INFO: possible circular locking
 dependency detected ]
In-Reply-To: <20121227083618.GA9775@S2101-09.ap.freescale.net>
References: <201212221628.26640.maciej.rutecki@gmail.com>
 <20121226023435.GE25478@S2101-09.ap.freescale.net>
 <20121227083618.GA9775@S2101-09.ap.freescale.net>
Message-ID: <1356613404.16896.4.camel@thor.lan>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Thu, 2012-12-27 at 16:36 +0800, Shawn Guo wrote:
> On Wed, Dec 26, 2012 at 10:34:39AM +0800, Shawn Guo wrote:
> > It seems that I'm running into the same locking issue.  My setup is:
> > 
> > - i.MX28 (ARM)
> > - v3.8-rc1
> > - mxs_defconfig
>   - The warning is seen when LCD is blanking
> > 
> 
> The warning disappears after reverting patch daee779 (console: implement
> lockdep support for console_lock).  Is it suggesting that the mxs
> frame buffer driver (drivers/video/mxsfb.c) is doing something bad?
> 
> Shawn
> 
> > 
> > [  602.229899] ======================================================
> > [  602.229905] [ INFO: possible circular locking dependency detected ]
> > [  602.229926] 3.8.0-rc1-00003-gde4ae7f #767 Not tainted
> > [  602.229933] -------------------------------------------------------
> > [  602.229951] kworker/0:1/21 is trying to acquire lock:
> > [  602.230037]  ((fb_notifier_list).rwsem){.+.+.+}, at: [<c0041f34>] __blocking_notifier_call_chain+0x2c/0x60

You want this patch https://patchwork.kernel.org/patch/1757061/