[PATCH 2.6.32 21/62] md/raid5: dont record new size if resize_stripes fails.

From	Willy Tarreau <w@1wt.eu>
Newsgroups	linux.kernel
Subject	[PATCH 2.6.32 21/62] md/raid5: dont record new size if resize_stripes fails.
Date	2015-09-13 01:30 +0200
Message-ID	<q82p5-6WW-61@gated-at.bofh.it> (permalink)
References	<q82fn-6Lq-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

2.6.32-longterm review patch.  If anyone has any objections, please let me know.

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

From: NeilBrown <neilb@suse.de>

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: Ben Hutchings <ben@decadent.org.uk>
(cherry picked from commit c20694a054e903745591f4f85b39ecbce4e58349)

Signed-off-by: Willy Tarreau <w@1wt.eu>
---
 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 4d70eef..7eb8b46 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1452,7 +1452,8 @@ static int resize_stripes(raid5_conf_t *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;
 }
 
-- 
1.7.12.2.21.g234cd45.dirty



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next | Find similar | Unroll thread

Thread

[PATCH 2.6.32 21/62] md/raid5: dont record new size if resize_stripes  fails. Willy Tarreau <w@1wt.eu> - 2015-09-13 01:30 +0200

csiph-web