Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754090Ab1EJGnA (ORCPT ); Tue, 10 May 2011 02:43:00 -0400 Received: from mx1.redhat.com ([209.132.183.28]:61051 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753589Ab1EJGm7 (ORCPT ); Tue, 10 May 2011 02:42:59 -0400 Date: Tue, 10 May 2011 12:12:47 +0530 From: Amit Shah To: Jens Axboe Cc: Tejun Heo , David Zeuthen , Martin Pitt , Kay Sievers , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] cdrom: always check_disk_change() on open Message-ID: <20110510064247.GA16436@amit-x200.redhat.com> References: <20110406121920.GC4142@mtj.dyndns.org> <20110429060200.GA5107@amit-x200.redhat.com> <4DBA73B6.6040603@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4DBA73B6.6040603@kernel.dk> 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 Content-Length: 1765 Lines: 42 On (Fri) 29 Apr 2011 [10:15:50], Jens Axboe wrote: > On 2011-04-29 08:57, Amit Shah wrote: > > On (Wed) 06 Apr 2011 [05:20:09], Tejun Heo wrote: > >> cdrom_open() called check_disk_change() after the rest of open path > >> succeeded which leads to the following bizarre behavior. > >> > >> * After media change, if the device opened without O_NONBLOCK, > >> open_for_data() naturally fails with -ENOMEDIA and > >> check_disk_change() is never called. The media is known to be gone > >> and the open failure makes it obvious to the userland but device > >> invalidation never happens. > >> > >> * But if the device is opened with O_NONBLOCK, all the checks are > >> bypassed and cdrom_open() doesn't notice that the media is not there > >> and check_disk_change() is called and invalidation happens. > >> > >> There's nothing to be gained by avoiding calling check_disk_change() > >> on open failure. Common cases end up calling check_disk_change() > >> anyway. All we get is inconsistent behavior. > >> > >> Fix it by moving check_disk_change() invocation to the top of > >> cdrom_open() so that it always gets called regardless of how the rest > >> of open proceeds. > >> > >> Signed-off-by: Tejun Heo > >> Reported-by: Amit Shah > >> Tested-by: Amit Shah > > > > Ping? > > > > Also, please mark this for stable-2.6.38. > > Done, added for 2.6.39 and marked stable for 2.6.38. Ping again. Don't see this yet in Linus's git tree. Amit -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/