This is a note to let you know that I've just added the patch titled
md: Avoid OOPS when reshaping raid1 to raid0
to the 3.3-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-avoid-oops-when-reshaping-raid1-to-raid0.patch
and it can be found in the queue-3.3 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.
>From 24b961f811a3e790a9b93604d2594bfb6cce4fa4 Mon Sep 17 00:00:00 2001
From: Jes Sorensen <[email protected]>
Date: Sun, 1 Apr 2012 23:48:38 +1000
Subject: md: Avoid OOPS when reshaping raid1 to raid0
From: Jes Sorensen <[email protected]>
commit 24b961f811a3e790a9b93604d2594bfb6cce4fa4 upstream.
raid1 arrays do not have the notion of chunk size. Calculate the
largest chunk sector size we can use to avoid a divide by zero OOPS
when aligning the size of the new array to the chunk size.
Signed-off-by: Jes Sorensen <[email protected]>
Signed-off-by: NeilBrown <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
drivers/md/raid0.c | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -609,6 +609,7 @@ static void *raid0_takeover_raid10(struc
static void *raid0_takeover_raid1(struct mddev *mddev)
{
struct r0conf *priv_conf;
+ int chunksect;
/* Check layout:
* - (N - 1) mirror drives must be already faulty
@@ -619,10 +620,25 @@ static void *raid0_takeover_raid1(struct
return ERR_PTR(-EINVAL);
}
+ /*
+ * a raid1 doesn't have the notion of chunk size, so
+ * figure out the largest suitable size we can use.
+ */
+ chunksect = 64 * 2; /* 64K by default */
+
+ /* The array must be an exact multiple of chunksize */
+ while (chunksect && (mddev->array_sectors & (chunksect - 1)))
+ chunksect >>= 1;
+
+ if ((chunksect << 9) < PAGE_SIZE)
+ /* array size does not allow a suitable chunk size */
+ return ERR_PTR(-EINVAL);
+
/* Set new parameters */
mddev->new_level = 0;
mddev->new_layout = 0;
- mddev->new_chunk_sectors = 128; /* by default set chunk size to 64k */
+ mddev->new_chunk_sectors = chunksect;
+ mddev->chunk_sectors = chunksect;
mddev->delta_disks = 1 - mddev->raid_disks;
mddev->raid_disks = 1;
/* make sure it will be not marked as dirty */
Patches currently in stable-queue which might be from [email protected]
are
queue-3.3/md-avoid-oops-when-reshaping-raid1-to-raid0.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
