From: NeilBrown Date: Fri, 10 Apr 2015 03:19:04 +0000 (+1000) Subject: md/raid0: fix bug with chunksize not a power of 2. X-Git-Tag: v4.1-rc1~21^2~22 X-Git-Url: https://git.kernel.dk/?p=linux-2.6-block.git;a=commitdiff_plain;h=47d68979cc968535cb87f3e5f2e6a3533ea48fbd md/raid0: fix bug with chunksize not a power of 2. 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 --- diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index 3ed9f42ddca6..3b5d7f704aa3 100644 --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -313,7 +313,7 @@ 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) @@ -524,6 +524,7 @@ 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;