From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760897AbXGEQnT (ORCPT ); Thu, 5 Jul 2007 12:43:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758380AbXGEQnH (ORCPT ); Thu, 5 Jul 2007 12:43:07 -0400 Received: from canuck.infradead.org ([209.217.80.40]:36287 "EHLO canuck.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758182AbXGEQnE (ORCPT ); Thu, 5 Jul 2007 12:43:04 -0400 Subject: Re: [1/2] 2.6.22-rc7: known regressions From: David Woodhouse To: Linus Torvalds Cc: Michal Piotrowski , marcel@holtmann.org, Andrew Morton , LKML , reiserfs-devel@vger.kernel.org, "Vladimir V. Saveliev" , Randy Dunlap , linux-ide@vger.kernel.org, David Chinner , sparclinux@vger.kernel.org, David Miller , Mikael Pettersson , Mark Fortescue , William Lee Irwin III In-Reply-To: References: <468A7D14.1050505@googlemail.com> <1183599771.2740.19.camel@shinybook.infradead.org> Content-Type: text/plain Date: Thu, 05 Jul 2007 12:43:22 -0400 Message-Id: <1183653802.2797.63.camel@shinybook.infradead.org> Mime-Version: 1.0 X-Mailer: Evolution 2.10.2 (2.10.2-2.fc7.dwmw2.1) Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by canuck.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2007-07-05 at 09:28 -0700, Linus Torvalds wrote: > > On Wed, 4 Jul 2007, David Woodhouse wrote: > > > > Oh, and here's another one for you. My Bluetooth mouse just stopped > > working and hidd is deadlocked... > > Looks like it is stuck on hidp_session_sem. > > Nothing after 2.6.21 seems to have even touched that semaphore usage, and > in fact there's not a whole lot of changes to the hidp code at all (and > none of them look even remotely interesting). > > So I suspect it's something lower down in the bluetooth stack, or it's a > long-standing problem that you are somehow able to trigger more easily > now. Is it consistent? It happened twice before I gave up on my 2.6.22-rc7 test kernel and went back to something earlier. I suppose I should double-check that it wasn't my slab changes, but I really don't think that's it. > Can you showo the traces for the _other_ processes that are in bluetooth > functions? Because there should be other processes there, holding that > hidp_session_sem rwsem. There was nothing, apart from a later 'hidd -l' which got stuck on the same semaphore. I have an hcidump of it happening, at http://david.woodhou.se/hidd-lockup-dump.txt -- it doesn't seem particularly enlightening though. There's just a disconnection and reconnect, as happens quite frequently with this mouse, and then we're deadlocked. I'll build with hidp debugging. -- dwmw2