From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:38928 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754081AbbEKL02 (ORCPT ); Mon, 11 May 2015 07:26:28 -0400 From: Sasha Levin To: stable@vger.kernel.org, stable-commits@vger.kernel.org Cc: NeilBrown , Sasha Levin Subject: [added to the 3.18 stable tree] md/raid0: fix bug with chunksize not a power of 2. Date: Mon, 11 May 2015 07:17:19 -0400 Message-Id: <1431343152-19437-58-git-send-email-sasha.levin@oracle.com> In-Reply-To: <1431343152-19437-1-git-send-email-sasha.levin@oracle.com> References: <1431343152-19437-1-git-send-email-sasha.levin@oracle.com> Sender: stable-owner@vger.kernel.org List-ID: From: NeilBrown This patch has been added to the 3.18 stable tree. If you have any objections, please let us know. =============== [ Upstream commit 47d68979cc968535cb87f3e5f2e6a3533ea48fbd ] Since commit 20d0189b1012a37d2533a87fb451f7852f2418d1 in v3.14-rc1 RAID0 has performed incorrect calculations when the chunksize is not a power of 2. This happens because "sector_div()" modifies its first argument, but this wasn't taken into account in the patch. So restore that first arg before re-using the variable. Reported-by: Joe Landman Reported-by: Dave Chinner Fixes: 20d0189b1012a37d2533a87fb451f7852f2418d1 Cc: stable@vger.kernel.org (3.14 and later). Signed-off-by: NeilBrown Signed-off-by: Sasha Levin --- drivers/md/raid0.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index ba6b85d..d5c12e5 100644 --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -319,7 +319,7 @@ static struct strip_zone *find_zone(struct r0conf *conf, /* * remaps the bio to the target device. we separate two flows. - * power 2 flow and a general flow for the sake of perfromance + * power 2 flow and a general flow for the sake of performance */ static struct md_rdev *map_sector(struct mddev *mddev, struct strip_zone *zone, sector_t sector, sector_t *sector_offset) @@ -537,6 +537,7 @@ static void raid0_make_request(struct mddev *mddev, struct bio *bio) split = bio; } + sector = bio->bi_iter.bi_sector; zone = find_zone(mddev->private, §or); tmp_dev = map_sector(mddev, zone, sector, §or); split->bi_bdev = tmp_dev->bdev; -- 2.1.0