In current code loop_lookup() is called from loop_probe(),
and loop_control_ioctl(). Each of these functions hold global
mutex lock loop_ctrl_mutex with two variants mutex_lock() and
mutex_lock_killable().
Add lockdep_asset_lock_held() in loop_lookup() to make sure it will
generate an appropriate error message in case of misuse.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx>
---
drivers/block/loop.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 3bfdcabaf6b1..0a8cee66c622 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -2211,6 +2211,8 @@ static int loop_lookup(struct loop_device **l, int i)
struct loop_device *lo;
int ret = -ENODEV;
+ lockdep_assert_held(&loop_ctl_mutex);
+
if (i < 0) {
int err;
--
2.22.1
