4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Michael Lyle <mlyle@xxxxxxxx> [ Upstream commit 6c4ca1e36cdc1a0a7a84797804b87920ccbebf51 ] register_shrinker is now __must_check, so check it to kill a warning. Caller of bch_btree_cache_alloc in super.c appropriately checks return value so this is fully plumbed through. This V2 fixes checkpatch warnings and improves the commit description, as I was too hasty getting the previous version out. Signed-off-by: Michael Lyle <mlyle@xxxxxxxx> Reviewed-by: Vojtech Pavlik <vojtech@xxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/md/bcache/btree.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -808,7 +808,10 @@ int bch_btree_cache_alloc(struct cache_s c->shrink.scan_objects = bch_mca_scan; c->shrink.seeks = 4; c->shrink.batch = c->btree_pages * 2; - register_shrinker(&c->shrink); + + if (register_shrinker(&c->shrink)) + pr_warn("bcache: %s: could not register shrinker", + __func__); return 0; }