From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Joe Landman , Dave Chinner , NeilBrown Subject: [PATCH 3.19 044/177] md/raid0: fix bug with chunksize not a power of 2. Date: Sat, 2 May 2015 21:01:06 +0200 Message-Id: <20150502190121.574249556@linuxfoundation.org> In-Reply-To: <20150502190119.666291882@linuxfoundation.org> References: <20150502190119.666291882@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: NeilBrown commit 47d68979cc968535cb87f3e5f2e6a3533ea48fbd upstream. 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 Signed-off-by: NeilBrown Signed-off-by: Greg Kroah-Hartman --- drivers/md/raid0.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -319,7 +319,7 @@ static struct strip_zone *find_zone(stru /* * 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 md 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;