From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752228Ab1ICWPf (ORCPT ); Sat, 3 Sep 2011 18:15:35 -0400 Received: from mail-iy0-f174.google.com ([209.85.210.174]:60806 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752048Ab1ICWPe (ORCPT ); Sat, 3 Sep 2011 18:15:34 -0400 Date: Sat, 3 Sep 2011 17:14:56 -0500 From: Jonathan Nieder To: Tejun Heo Cc: Jens Axboe , Amit Shah , David Zeuthen , Martin Pitt , Kay Sievers , linux-kernel@vger.kernel.org, Jean Schurger , Jan =?utf-8?B?TMO8YmJl?= , Matthijs Kooijman , Jameson Graef Rollins , Nacho Barrientos Arias Subject: [regression] CD-ROM polling blocks suspend on some machines (Re: [PATCH 1/2] cdrom: always check_disk_change() on open) Message-ID: <20110903221456.GA2877@elie> References: <20110406121920.GC4142@mtj.dyndns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110406121920.GC4142@mtj.dyndns.org> User-Agent: Mutt/1.5.21+46 (b01d63af6fea) (2011-07-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Various people[1] have been noticing a race (or races?) in which the cdrom_id and scsi_id programs from udev can get stuck in the D state if udev doesn't sleep a little while before running them. This prevents the machine from suspending. The problem was discovered with Debian kernels 2.6.39-1 2.6.39-2 3.0.0-1 and was not experienced with kernel 2.6.38-5 (These kernels are closely based on v2.6.39, v2.6.39.1, v3.0, and v2.6.38.5, respectively.) Reverting commit bf2253a6f00e (cdrom: always check_disk_change() on open, 2011-04-29) seems to avoid trouble. One common theme seems to be DVD drives. Details at [1]. Known problem? Any ideas for tracking it down? Looking forward to your thoughts, Jonathan [1] . Submitters cc-ed.