Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262275AbVDFSUY (ORCPT ); Wed, 6 Apr 2005 14:20:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262274AbVDFSUY (ORCPT ); Wed, 6 Apr 2005 14:20:24 -0400 Received: from stat16.steeleye.com ([209.192.50.48]:5785 "EHLO hancock.sc.steeleye.com") by vger.kernel.org with ESMTP id S262273AbVDFSUS (ORCPT ); Wed, 6 Apr 2005 14:20:18 -0400 Subject: Re: [OOPS] 2.6.11 - NMI lockup with CFQ scheduler From: James Bottomley To: Jens Axboe Cc: Chris Rankin , Linux Kernel , SCSI Mailing List In-Reply-To: <20050406175838.GC15165@suse.de> References: <20050329115405.97559.qmail@web52909.mail.yahoo.com> <20050329120311.GO16636@suse.de> <1112804840.5476.16.camel@mulgrave> <20050406175838.GC15165@suse.de> Content-Type: text/plain Date: Wed, 06 Apr 2005 14:20:07 -0400 Message-Id: <1112811607.5555.15.camel@mulgrave> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 (2.0.4-2) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1200 Lines: 26 On Wed, 2005-04-06 at 19:58 +0200, Jens Axboe wrote: > I rather like the queue lock being a pointer, so you can share at > whatever level you want. Lets not grow the request_queue a full lock > just to work around a bug elsewhere. I'm not proposing that it not be a pointer, merely that it could be intialiased to point to a lock structure within the request queue. Doing this looks much simpler than your current patch ... one of the problems with which looks to be that removing the scsi_driver module is in trouble because we currently have the queue_release in the sdev release (which won't get called while the queue holds a reference). I think the correct model for all of this is that the block driver shouldn't care (or be tied to) the scsi one. Thus, as long as SCSI can reject requests from a queue whose device has been released (without checking the device) then everything is fine as long as we sort out the lock lifetime problem. James - 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/