1 files changed, 6 insertions, 4 deletions

diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index d1a3b2cfe4a9..b739be2a6dc9 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -1176,7 +1176,7 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)
  * itself, so actual lookup of the hash should be once per lock object.
  */
 static inline struct lock_class *
-register_lock_class(struct lockdep_map *lock, unsigned int subclass)
+register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)
 {
         struct lockdep_subclass_key *key;
         struct list_head *hash_head;
@@ -1248,7 +1248,7 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass)
 out_unlock_set:
         __raw_spin_unlock(&hash_lock);
 
-        if (!subclass)
+        if (!subclass || force)
                 lock->class_cache = class;
 
         DEBUG_LOCKS_WARN_ON(class->subclass != subclass);
@@ -1936,7 +1936,7 @@ void trace_softirqs_off(unsigned long ip)
  * Initialize a lock instance's lock-class mapping info:
  */
 void lockdep_init_map(struct lockdep_map *lock, const char *name,
-                      struct lock_class_key *key)
+                      struct lock_class_key *key, int subclass)
 {
         if (unlikely(!debug_locks))
                 return;
@@ -1956,6 +1956,8 @@ void lockdep_init_map(struct lockdep_map *lock, const char *name,
         lock->name = name;
         lock->key = key;
         lock->class_cache = NULL;
+        if (subclass)
+                register_lock_class(lock, subclass, 1);
 }
 
 EXPORT_SYMBOL_GPL(lockdep_init_map);
@@ -1994,7 +1996,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
          * Not cached yet or subclass?
          */
         if (unlikely(!class)) {
-                class = register_lock_class(lock, subclass);
+                class = register_lock_class(lock, subclass, 0);
                 if (!class)
                         return 0;
         }