[PATCH 3.4 087/146] md/raid5: don't record new size if resize_stripes fails.

lizf
2015-09-15T09:29:47Z

From: NeilBrown <neilb@suse.de>

3.4.109-rc1 review patch. If anyone has any objections, please let me know.

------------------

commit 6e9eac2dcee5e19f125967dd2be3e36558c42fff upstream.

If any memory allocation in resize_stripes fails we will return
-ENOMEM, but in some cases we update conf->pool_size anyway.

This means that if we try again, the allocations will be assumed
to be larger than they are, and badness results.

So only update pool_size if there is no error.

This bug was introduced in 2.6.17 and the patch is suitable for
-stable.

Fixes: ad01c9e3752f ("[PATCH] md: Allow stripes to be expanded in preparation for expanding an array")
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Zefan Li <lizefan@huawei.com>
---
drivers/md/raid5.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index c276ad0..7a218e8 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1622,7 +1622,8 @@ static int resize_stripes(struct r5conf *conf, int newsize)

conf->slab_cache = sc;
conf->active_name = 1-conf->active_name;
- conf->pool_size = newsize;
+ if (!err)
+ conf->pool_size = newsize;
return err;
}

--
1.9.1