From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753400Ab2GWBnL (ORCPT ); Sun, 22 Jul 2012 21:43:11 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:54288 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753239Ab2GWBnH (ORCPT ); Sun, 22 Jul 2012 21:43:07 -0400 Message-Id: <20120723010701.303457284@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Mon, 23 Jul 2012 02:07:56 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, NeilBrown , Alexander Lyakas Subject: [ 065/108] md/raid1: close some possible races on write errors during resync In-Reply-To: <20120723010651.408577075@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 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 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: NeilBrown commit 58e94ae18478c08229626daece2fc108a4a23261 upstream. commit 4367af556133723d0f443e14ca8170d9447317cb md/raid1: clear bad-block record when write succeeds. Added a 'reschedule_retry' call possibility at the end of end_sync_write, but didn't add matching code at the end of sync_request_write. So if the writes complete very quickly, or scheduling makes it seem that way, then we can miss rescheduling the request and the resync could hang. Also commit 73d5c38a9536142e062c35997b044e89166e063b md: avoid races when stopping resync. Fix a race condition in this same code in end_sync_write but didn't make the change in sync_request_write. This patch updates sync_request_write to fix both of those. Patch is suitable for 3.1 and later kernels. Reported-by: Alexander Lyakas Original-version-by: Alexander Lyakas Signed-off-by: NeilBrown Signed-off-by: Ben Hutchings --- drivers/md/raid1.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 240ff31..cacd008 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1818,8 +1818,14 @@ static void sync_request_write(struct mddev *mddev, struct r1bio *r1_bio) if (atomic_dec_and_test(&r1_bio->remaining)) { /* if we're here, all write(s) have completed, so clean up */ - md_done_sync(mddev, r1_bio->sectors, 1); - put_buf(r1_bio); + int s = r1_bio->sectors; + if (test_bit(R1BIO_MadeGood, &r1_bio->state) || + test_bit(R1BIO_WriteError, &r1_bio->state)) + reschedule_retry(r1_bio); + else { + put_buf(r1_bio); + md_done_sync(mddev, s, 1); + } } }