diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 4c0553461000..805a322a5655 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -1114,8 +1114,6 @@ static int count_matching_names(struct lock_class *new_class)
 	return count + 1;
 }
 
-extern void __error_too_big_MAX_LOCKDEP_SUBCLASSES(void);
-
 /*
  * Register a lock's class in the hash-table, if the class is not present
  * yet. Otherwise we look it up. We cache the result in the lock object
@@ -1153,8 +1151,7 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)
 	 * (or spin_lock_init()) call - which acts as the key. For static
 	 * locks we use the lock object itself as the key.
 	 */
-	if (sizeof(struct lock_class_key) > sizeof(struct lock_class))
-		__error_too_big_MAX_LOCKDEP_SUBCLASSES();
+	BUILD_BUG_ON(sizeof(struct lock_class_key) > sizeof(struct lock_class));
 
 	key = lock->key->subkeys + subclass;