From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:44466 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933674AbeCGRhB (ORCPT ); Wed, 7 Mar 2018 12:37:01 -0500 Subject: Patch "dm io: fix duplicate bio completion due to missing ref count" has been added to the 4.9-stable tree To: snitzer@redhat.com, gregkh@linuxfoundation.org, yizhan@redhat.com Cc: , From: Date: Wed, 07 Mar 2018 09:36:59 -0800 Message-ID: <1520444219635@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled dm io: fix duplicate bio completion due to missing ref count to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: dm-io-fix-duplicate-bio-completion-due-to-missing-ref-count.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From feb7695fe9fb83084aa29de0094774f4c9d4c9fc Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Tue, 20 Jun 2017 19:14:30 -0400 Subject: dm io: fix duplicate bio completion due to missing ref count From: Mike Snitzer commit feb7695fe9fb83084aa29de0094774f4c9d4c9fc upstream. If only a subset of the devices associated with multiple regions support a given special operation (eg. DISCARD) then the dec_count() that is used to set error for the region must increment the io->count. Otherwise, when the dec_count() is called it can cause the dm-io caller's bio to be completed multiple times. As was reported against the dm-mirror target that had mirror legs with a mix of discard capabilities. Bug: https://bugzilla.kernel.org/show_bug.cgi?id=196077 Reported-by: Zhang Yi Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-io.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/md/dm-io.c +++ b/drivers/md/dm-io.c @@ -302,6 +302,7 @@ static void do_region(int op, int op_fla special_cmd_max_sectors = q->limits.max_write_same_sectors; if ((op == REQ_OP_DISCARD || op == REQ_OP_WRITE_SAME) && special_cmd_max_sectors == 0) { + atomic_inc(&io->count); dec_count(io, region, -EOPNOTSUPP); return; } Patches currently in stable-queue which might be from snitzer@redhat.com are queue-4.9/dm-io-fix-duplicate-bio-completion-due-to-missing-ref-count.patch