From: Wei Fang Date: Mon, 21 Mar 2016 11:18:32 +0000 (+0800) Subject: md:raid1: fix a dead loop when read from a WriteMostly disk X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=816b0acf3deb6d6be5d0519b286fdd4bafade905;p=openwrt%2Fstaging%2Fblogic.git md:raid1: fix a dead loop when read from a WriteMostly disk 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 --- diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 39fb21e048e6..a7f2b9c9f8a0 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;