On Mon, Jun 21, 2021 at 10:21:14AM +0900, Naohiro Aota wrote:

qgroup_account_snapshot() is trying to unlock the not taken
tree_log_mutex in a error path. Since ret != 0 in this case, we can
just return from here.

Fixes: 2a4d84c11a87 ("btrfs: move delayed ref flushing for qgroup into qgroup helper")
Cc: stable <redacted> # 5.12
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>

Added to misc-next, thanks.