Patch "md/raid0: fix bug with chunksize not a power of 2." has been added to the 3.14-stable tree

Patch "md/raid0: fix bug with chunksize not a power of 2." has been added to the 3.14-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    md/raid0: fix bug with chunksize not a power of 2.

to the 3.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     md-raid0-fix-bug-with-chunksize-not-a-power-of-2.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 47d68979cc968535cb87f3e5f2e6a3533ea48fbd Mon Sep 17 00:00:00 2001
From: NeilBrown <neilb@suse.de>
Date: Fri, 10 Apr 2015 13:19:04 +1000
Subject: md/raid0: fix bug with chunksize not a power of 2.

From: NeilBrown <neilb@suse.de>

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 <joe.landman@gmail.com>
Reported-by: Dave Chinner <david@fromorbit.com>
Fixes: 20d0189b1012a37d2533a87fb451f7852f2418d1
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/md/raid0.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -320,7 +320,7 @@ 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)
@@ -538,6 +538,7 @@ static void raid0_make_request(struct md
 			split = bio;
 		}
 
+		sector = bio->bi_iter.bi_sector;
 		zone = find_zone(mddev->private, &sector);
 		tmp_dev = map_sector(mddev, zone, sector, &sector);
 		split->bi_bdev = tmp_dev->bdev;


Patches currently in stable-queue which might be from neilb@suse.de are

queue-3.14/md-raid0-fix-bug-with-chunksize-not-a-power-of-2.patch