From: weiping zhang <zhangweiping@didichuxing.com>
Date: Tue, 31 Oct 2017 10:38:59 +0000 (+0800)
Subject: block: add WARN_ON if bdi register fail
X-Git-Tag: v4.15-rc2~12^2~16
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=3a92168bc8a113098b44a95d499557a88bb387da;p=uclinux-h8%2Flinux.git

block: add WARN_ON if bdi register fail

device_add_disk need do more safety error handle, so this patch just
add WARN_ON.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>

Adapted for current series by me.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/block/genhd.c b/block/genhd.c
index c2223f12a805..c143a2274238 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -671,10 +671,13 @@ void device_add_disk(struct device *parent, struct gendisk *disk)
 		disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO;
 		disk->flags |= GENHD_FL_NO_PART_SCAN;
 	} else {
+		int ret;
+
 		/* Register BDI before referencing it from bdev */
 		disk_to_dev(disk)->devt = devt;
-		bdi_register_owner(disk->queue->backing_dev_info,
-				disk_to_dev(disk));
+		ret = bdi_register_owner(disk->queue->backing_dev_info,
+						disk_to_dev(disk));
+		WARN_ON(ret);
 		blk_register_region(disk_devt(disk), disk->minors, NULL,
 				    exact_match, exact_lock, disk);
 	}