From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756222Ab2CLSMP (ORCPT ); Mon, 12 Mar 2012 14:12:15 -0400 Received: from mail-pz0-f46.google.com ([209.85.210.46]:55946 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755532Ab2CLSMO (ORCPT ); Mon, 12 Mar 2012 14:12:14 -0400 Date: Mon, 12 Mar 2012 11:12:08 -0700 From: Tejun Heo To: Sasha Levin Cc: axboe@kernel.dk, linux-kernel@vger.kernel.org, Vivek Goyal Subject: Re: [PATCH] blk-cgroup: Call cgroup_path only under cgroup lock Message-ID: <20120312181208.GD23255@google.com> References: <1331582478-2259-1-git-send-email-levinsasha928@gmail.com> <20120312180423.GC23255@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 12, 2012 at 08:06:53PM +0200, Sasha Levin wrote: > On Mon, Mar 12, 2012 at 8:04 PM, Tejun Heo wrote: > > Hello, Sasha. > > > > On Mon, Mar 12, 2012 at 04:01:18PM -0400, Sasha Levin wrote: > >> Since we can't keep rcu read lock during blkg_alloc(), we currently > >> call cgroup_path() without any locks at all. > >> > >> This patch adds cgroup locking before calling cgroup_path. > >> > >> This also fixes a lockdep warning on boot. > >> > >> Signed-off-by: Sasha Levin > > > > Which branch is this against?  There's already pending stat update > > patch from Vivek which fix this problem along with the percpu > > allocation problem. > > > > Thanks. > > I've fixed it for linux-next. Jens, the pending stats patchset should fix this problem too. Can you please put them on top of other blkcg updates? Thanks. -- tejun