From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753277AbaBGTxS (ORCPT ); Fri, 7 Feb 2014 14:53:18 -0500 Received: from mail-qa0-f51.google.com ([209.85.216.51]:43338 "EHLO mail-qa0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751013AbaBGTxR (ORCPT ); Fri, 7 Feb 2014 14:53:17 -0500 Date: Fri, 7 Feb 2014 14:53:13 -0500 From: Tejun Heo To: Imre Deak Cc: Greg Kroah-Hartman , Borislav Petkov , linux-kernel@vger.kernel.org Subject: Re: [PATCH] kernfs: skip lockdep annotation always if ignore_lockdep is set Message-ID: <20140207195313.GB8833@htj.dyndns.org> References: <1391802421-7829-1-git-send-email-imre.deak@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1391802421-7829-1-git-send-email-imre.deak@intel.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 07, 2014 at 09:47:01PM +0200, Imre Deak wrote: > We skip lockdep annotations for sysfs attributes with ignore_lockdep > set. An exception is kernfs_deactivate where we annotate even in this > case. Since the lockdep map key needed for the annotation is not > initialized whenever ignore_lockdep is set, we'll get a warning for > the uninitialized key. > > Note that this happens since, > > commit 517e64f57883bd63c5a4ab8b3d0d3ed68c55d0cf > Author: Tejun Heo > Date: Thu Nov 28 14:54:29 2013 -0500 > > Before this change we had a valid key even in case of ignore_lockdep, so > the annotation in kernfs_deactivate worked, or at least didn't produce > the above warning. Fix this by skipping the annotation whenever > ignore_lockdep is set. > > The actual attribute triggering the bug was 'delete_device' in > drivers/i2c/i2c-core.c, for the backtrace see the reference below. I think Greg already has about the same patch queued. http://lkml.kernel.org/g/20140129170403.GJ30842@htj.dyndns.org Thanks. -- tejun