[PATCH 4/4] block: add WARN_ON if bdi register fail

[weiping zhang]

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

Signed-off-by: weiping zhang <zhangweip...@didichuxing.com>
---
 block/genhd.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/block/genhd.c b/block/genhd.c
index dd305c65ffb0..cb55eea821eb 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -660,7 +660,9 @@ void device_add_disk(struct device *parent, struct gendisk 
*disk)
 
        /* Register BDI before referencing it from bdev */
        bdi = disk->queue->backing_dev_info;
-       bdi_register_owner(bdi, disk_to_dev(disk));
+       retval = bdi_register_owner(bdi, disk_to_dev(disk));
+       if (retval)
+               WARN_ON(1);
 
        blk_register_region(disk_devt(disk), disk->minors, NULL,
                            exact_match, exact_lock, disk);
-- 
2.14.2