Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934268AbbHJKR4 (ORCPT ); Mon, 10 Aug 2015 06:17:56 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:44198 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934248AbbHJKRv (ORCPT ); Mon, 10 Aug 2015 06:17:51 -0400 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, "Dennis Yang" , "Joe Thornber" , "Mike Snitzer" Date: Mon, 10 Aug 2015 12:12:31 +0200 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 068/110] dm btree remove: fix bug in redistribute3 In-Reply-To: X-SA-Exim-Connect-IP: 2.173.94.72 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 Content-Length: 1747 Lines: 52 3.2.71-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Dennis Yang commit 4c7e309340ff85072e96f529582d159002c36734 upstream. redistribute3() shares entries out across 3 nodes. Some entries were being moved the wrong way, breaking the ordering. This manifested as a BUG() in dm-btree-remove.c:shift() when entries were removed from the btree. For additional context see: https://www.redhat.com/archives/dm-devel/2015-May/msg00113.html Signed-off-by: Dennis Yang Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Signed-off-by: Ben Hutchings --- drivers/md/persistent-data/dm-btree-remove.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/md/persistent-data/dm-btree-remove.c +++ b/drivers/md/persistent-data/dm-btree-remove.c @@ -309,8 +309,8 @@ static void redistribute3(struct dm_btre if (s < 0 && nr_center < -s) { /* not enough in central node */ - shift(left, center, nr_center); - s = nr_center - target; + shift(left, center, -nr_center); + s += nr_center; shift(left, right, s); nr_right += s; } else @@ -323,7 +323,7 @@ static void redistribute3(struct dm_btre if (s > 0 && nr_center < s) { /* not enough in central node */ shift(center, right, nr_center); - s = target - nr_center; + s -= nr_center; shift(left, right, s); nr_left -= s; } else -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/