From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH] SCSI: Fix some locking issues Date: Wed, 2 Jul 2008 13:50:31 +0200 Message-ID: <20080702115030.GK20055@kernel.dk> References: <877ic8o4iq.fsf@denkblock.local> <87prpxnv4w.fsf@denkblock.local> <1214963700.3316.41.camel@localhost.localdomain> <87zlp0n4p8.fsf@denkblock.local> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from brick.kernel.dk ([87.55.233.238]:23397 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1764071AbYGBLud (ORCPT ); Wed, 2 Jul 2008 07:50:33 -0400 Content-Disposition: inline In-Reply-To: <87zlp0n4p8.fsf@denkblock.local> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Elias Oltmanns Cc: James Bottomley , linux-scsi@vger.kernel.org, stable@kernel.org On Wed, Jul 02 2008, Elias Oltmanns wrote: > > The blk_plug_queue change looks reasonable ... however, blk_plug_queue > > itself looks like it might not entirely need the queue lock ... I need > > to investigate more closely. > > Well, I rather think it does. We have to serialise access to the > unplug_timer and there is a call to __set_bit() which, as I understand, > requires the calling function to ensure atomicity. Yep, blk_plug_device() needs to be called with the queue lock held. -- Jens Axboe