Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757999Ab1DMRBZ (ORCPT ); Wed, 13 Apr 2011 13:01:25 -0400 Received: from bedivere.hansenpartnership.com ([66.63.167.143]:48961 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757952Ab1DMRBX (ORCPT ); Wed, 13 Apr 2011 13:01:23 -0400 Subject: Re: Strange block/scsi/workqueue issue From: James Bottomley To: Steven Whitehouse Cc: Tejun Heo , linux-kernel@vger.kernel.org, Jens Axboe In-Reply-To: <1302703208.2613.18.camel@dolmen> References: <1302621261.2604.18.camel@mulgrave.site> <1302624266.2661.21.camel@dolmen> <1302625621.2604.24.camel@mulgrave.site> <1302627097.2661.25.camel@dolmen> <1302630090.2604.30.camel@mulgrave.site> <1302633208.2661.29.camel@dolmen> <1302638216.2604.35.camel@mulgrave.site> <1302640226.2661.34.camel@dolmen> <1302641036.2604.40.camel@mulgrave.site> <20110413051846.GD24161@mtj.dyndns.org> <20110413060651.GA27823@mtj.dyndns.org> <1302686454.2613.4.camel@dolmen> <1302703208.2613.18.camel@dolmen> Content-Type: text/plain; charset="UTF-8" Date: Wed, 13 Apr 2011 12:01:20 -0500 Message-ID: <1302714080.2597.29.camel@mulgrave.site> Mime-Version: 1.0 X-Mailer: Evolution 2.32.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2086 Lines: 66 While you still have the problematic system, can you try this patch? It avoids changing anything in block (other than to add a missing state guard for the elv_next_request). If it works, we can defer the sync vs async discussion and use it for a -stable fix. Thanks, James --- diff --git a/block/blk.h b/block/blk.h index c8db371..11d0d25 100644 --- a/block/blk.h +++ b/block/blk.h @@ -62,7 +62,8 @@ static inline struct request *__elv_next_request(struct request_queue *q) return rq; } - if (!q->elevator->ops->elevator_dispatch_fn(q, 0)) + if (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags) || + !q->elevator->ops->elevator_dispatch_fn(q, 0)) return NULL; } } diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index e44ff64..5aa4246 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -322,14 +322,9 @@ static void scsi_device_dev_release_usercontext(struct work_struct *work) kfree(evt); } - if (sdev->request_queue) { - sdev->request_queue->queuedata = NULL; - /* user context needed to free queue */ - scsi_free_queue(sdev->request_queue); - /* temporary expedient, try to catch use of queue lock - * after free of sdev */ - sdev->request_queue = NULL; - } + /* temporary expedient, try to catch use of queue lock after + * free of sdev */ + sdev->request_queue = NULL; scsi_target_reap(scsi_target(sdev)); @@ -937,6 +932,11 @@ void __scsi_remove_device(struct scsi_device *sdev) if (sdev->host->hostt->slave_destroy) sdev->host->hostt->slave_destroy(sdev); transport_destroy_device(dev); + /* Setting this to NULL causes the request function to reject + * any I/O requests */ + sdev->request_queue->queuedata = NULL; + /* Freeing the queue signals to block that we're done */ + scsi_free_queue(sdev->request_queue); put_device(dev); } -- 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/