From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933194AbcCGX3d (ORCPT ); Mon, 7 Mar 2016 18:29:33 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:39486 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753896AbcCGWy6 (ORCPT ); Mon, 7 Mar 2016 17:54:58 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Mike Snitzer , Kamal Mostafa Subject: [PATCH 4.2.y-ckt 192/273] dm: fix dm_rq_target_io leak on faults with .request_fn DM w/ blk-mq paths Date: Mon, 7 Mar 2016 14:49:43 -0800 Message-Id: <1457391064-6660-193-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1457391064-6660-1-git-send-email-kamal@canonical.com> References: <1457391064-6660-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 4.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.2.8-ckt5 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Mike Snitzer commit 4328daa2e79ed904a42ce00a9f38b9c36b44b21a upstream. Using request-based DM mpath configured with the following stacking (.request_fn DM mpath ontop of scsi-mq paths): echo Y > /sys/module/scsi_mod/parameters/use_blk_mq echo N > /sys/module/dm_mod/parameters/use_blk_mq 'struct dm_rq_target_io' would leak if a request is requeued before a blk-mq clone is allocated (or fails to allocate). free_rq_tio() wasn't being called. kmemleak reported: unreferenced object 0xffff8800b90b98c0 (size 112): comm "kworker/7:1H", pid 5692, jiffies 4295056109 (age 78.589s) hex dump (first 32 bytes): 00 d0 5c 2c 03 88 ff ff 40 00 bf 01 00 c9 ff ff ..\,....@....... e0 d9 b1 34 00 88 ff ff 00 00 00 00 00 00 00 00 ...4............ backtrace: [] kmemleak_alloc+0x4e/0xb0 [] kmem_cache_alloc+0xc3/0x1e0 [] mempool_alloc_slab+0x15/0x20 [] mempool_alloc+0x6e/0x170 [] dm_old_prep_fn+0x3c/0x180 [dm_mod] [] blk_peek_request+0x168/0x290 [] dm_request_fn+0xb2/0x1b0 [dm_mod] [] __blk_run_queue+0x33/0x40 [] blk_delay_work+0x25/0x40 [] process_one_work+0x14f/0x3d0 [] worker_thread+0x125/0x4b0 [] kthread+0xd8/0xf0 [] ret_from_fork+0x3f/0x70 [] 0xffffffffffffffff crash> struct -o dm_rq_target_io struct dm_rq_target_io { ... } SIZE: 112 Fixes: e5863d9ad7 ("dm: allocate requests in target when stacking on blk-mq devices") Signed-off-by: Mike Snitzer Signed-off-by: Kamal Mostafa --- drivers/md/dm.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index e0bf361..3f82998 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1161,6 +1161,8 @@ static void dm_unprep_request(struct request *rq) if (clone) free_rq_clone(clone); + else if (!tio->md->queue->mq_ops) + free_rq_tio(tio); } /* -- 2.7.0