From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S942514AbcJZMzR (ORCPT ); Wed, 26 Oct 2016 08:55:17 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:55875 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966748AbcJZMd2 (ORCPT ); Wed, 26 Oct 2016 08:33:28 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Bart Van Assche , Mike Snitzer Subject: [PATCH 4.4 024/112] dm mpath: check if paths request_queue is dying in activate_path() Date: Wed, 26 Oct 2016 14:22:07 +0200 Message-Id: <20161026122305.812832912@linuxfoundation.org> X-Mailer: git-send-email 2.10.1 In-Reply-To: <20161026122304.797016625@linuxfoundation.org> References: <20161026122304.797016625@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mike Snitzer commit f10e06b744074824fb8ec7066bc03ecc90918f5b upstream. If pg_init_retries is set and a request is queued against a multipath device with all underlying block device request_queues in the "dying" state then an infinite loop is triggered because activate_path() never succeeds and hence never calls pg_init_done(). This change avoids that device removal triggers an infinite loop by failing the activate_path() which causes the "dying" path to be failed. Reported-by: Bart Van Assche Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-mpath.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -1220,10 +1220,10 @@ static void activate_path(struct work_st { struct pgpath *pgpath = container_of(work, struct pgpath, activate_path.work); + struct request_queue *q = bdev_get_queue(pgpath->path.dev->bdev); - if (pgpath->is_active) - scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev), - pg_init_done, pgpath); + if (pgpath->is_active && !blk_queue_dying(q)) + scsi_dh_activate(q, pg_init_done, pgpath); else pg_init_done(pgpath, SCSI_DH_DEV_OFFLINED); }