diff --git a/drivers/staging/comedi/drivers.c b/drivers/staging/comedi/drivers.c
index fdf0a5761f9b..750a6ff3c03c 100644
--- a/drivers/staging/comedi/drivers.c
+++ b/drivers/staging/comedi/drivers.c
@@ -159,6 +159,7 @@ static void comedi_device_detach_cleanup(struct comedi_device *dev)
 	int i;
 	struct comedi_subdevice *s;
 
+	lockdep_assert_held(&dev->attach_lock);
 	lockdep_assert_held(&dev->mutex);
 	if (dev->subdevices) {
 		for (i = 0; i < dev->n_subdevices; i++) {