From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756787Ab2HNRoh (ORCPT ); Tue, 14 Aug 2012 13:44:37 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:29808 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754939Ab2HNRof (ORCPT ); Tue, 14 Aug 2012 13:44:35 -0400 X-Authority-Analysis: v=2.0 cv=LIjkseq9 c=1 sm=0 a=s5Htg7xnQOKvHEu9STBOug==:17 a=OpT9cpI26MMA:10 a=HMINAUNbf7oA:10 a=5SG0PmZfjMsA:10 a=Q9fys5e9bTEA:10 a=meVymXHHAAAA:8 a=ayC55rCoAAAA:8 a=TNLAKgqMk2JoBKEYc2wA:9 a=PUjeQqilurYA:10 a=s5Htg7xnQOKvHEu9STBOug==:117 X-Cloudmark-Score: 0 X-Originating-IP: 72.230.195.127 Message-ID: <1344966273.6724.18.camel@gandalf.stny.rr.com> Subject: Re: [rfc patch] fs,reiserfs: unlock superblock before callling reiserfs_quota_on_mount() From: Steven Rostedt To: Mike Galbraith Cc: Thomas Gleixner , "linux-rt-users@vger.kernel.org" , Frederic Weisbecker , LKML Date: Tue, 14 Aug 2012 13:44:33 -0400 In-Reply-To: <1344965173.4282.3.camel@marge.simpson.net> References: <1344949583.14924.36.camel@marge.simpson.net> <1344954183.6724.8.camel@gandalf.stny.rr.com> <1344955168.14924.85.camel@marge.simpson.net> <1344956189.5477.1.camel@marge.simpson.net> <1344965173.4282.3.camel@marge.simpson.net> Content-Type: text/plain; charset="ISO-8859-15" X-Mailer: Evolution 3.4.3-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2012-08-14 at 19:26 +0200, Mike Galbraith wrote: > On Tue, 2012-08-14 at 17:18 +0200, Thomas Gleixner wrote: > > On Tue, 14 Aug 2012, Mike Galbraith wrote: > > > > > On Tue, 2012-08-14 at 16:39 +0200, Mike Galbraith wrote: > > > > On Tue, 2012-08-14 at 10:23 -0400, Steven Rostedt wrote: > > > > > On Tue, 2012-08-14 at 15:06 +0200, Mike Galbraith wrote: > > > > > > Greetings, > > > > > > > > > > > > Using openSUSE's "partitioner" gizmo to set up a reiserfs partition with > > > > > > quotas and whatnot enabled rewarded me with a deadlock. > > > > > > > > > > Is this just a -rt bug? Can't this deadlock also in mainline? > > > > > > > > It didn't with a NOPREEMPT kernel the one time I tried it, which seemed > > > > mighty odd when I stared at the rt deadlock. I'll give it another go, I > > > > likely just munged q/d NOPREEMPT test. > > > > > > Nope, no screw-up. Maybe it can deadlock, but it refused to do so. > > > > Lockdep should tell you if it could ... > > I'll give that a shot. I would expect the thing to gripe.. but then I > expected the damn thing to deadlock properly with NOPREEMPT too, so.. :) > But would it? We have kworker blocked on the mutex where the owner did a flush_work(), and waiting for kworker to finish because of a wait_for_completion(). I don't see annotation here that will help lockdep catch such a thing. -- Steve