From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755966AbdBPABA (ORCPT ); Wed, 15 Feb 2017 19:01:00 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:53697 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753158AbdBOXSU (ORCPT ); Wed, 15 Feb 2017 18:18:20 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Mike Snitzer" , "Bart Van Assche" Date: Wed, 15 Feb 2017 22:41:40 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 045/306] dm mpath: check if path's request_queue is dying in activate_path() In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.40-rc1 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: Ben Hutchings --- 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 @@ -1196,10 +1196,10 @@ 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); }