diff --git a/include/linux/reservation.h b/include/linux/reservation.h
index 2f0ffca35780..ee750765cc94 100644
--- a/include/linux/reservation.h
+++ b/include/linux/reservation.h
@@ -228,7 +228,8 @@ reservation_object_unlock(struct reservation_object *obj)
  * @obj: the reservation object
  *
  * Returns the exclusive fence (if any).  Does NOT take a
- * reference.  The obj->lock must be held.
+ * reference. Writers must hold obj->lock, readers may only
+ * hold a RCU read side lock.
  *
  * RETURNS
  * The exclusive fence or NULL