From 49b2fe4b020776640268a5d75c5eca712fcc7b01 Mon Sep 17 00:00:00 2001 From: Wei Fang Date: Mon, 21 Mar 2016 19:18:32 +0800 Subject: md:raid1: fix a dead loop when read from a WriteMostly disk commit 816b0acf3deb6d6be5d0519b286fdd4bafade905 upstream. If first_bad == this_sector when we get the WriteMostly disk in read_balance(), valid disk will be returned with zero max_sectors. It'll lead to a dead loop in make_request(), and OOM will happen because of endless allocation of struct bio. Since we can't get data from this disk in this case, so continue for another disk. Signed-off-by: Wei Fang Signed-off-by: Shaohua Li Cc: Julia Lawall Signed-off-by: Greg Kroah-Hartman --- drivers/md/raid1.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/md') diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 9be39988bf06..d81be5e471d0 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -570,7 +570,7 @@ static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sect if (best_dist_disk < 0) { if (is_badblock(rdev, this_sector, sectors, &first_bad, &bad_sectors)) { - if (first_bad < this_sector) + if (first_bad <= this_sector) /* Cannot use this */ continue; best_good_sectors = first_bad - this_sector; -- cgit v1.2.3