1 files changed, 14 insertions, 12 deletions

diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 4c0553461000..c9fefdb1a7db 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -575,6 +575,8 @@ static noinline int print_circular_bug_tail(void)
         return 0;
 }
 
+#define RECURSION_LIMIT 40
+
 static int noinline print_infinite_recursion_bug(void)
 {
         __raw_spin_unlock(&hash_lock);
@@ -595,7 +597,7 @@ check_noncircular(struct lock_class *source, unsigned int depth)
         debug_atomic_inc(&nr_cyclic_check_recursions);
         if (depth > max_recursion_depth)
                 max_recursion_depth = depth;
-        if (depth >= 20)
+        if (depth >= RECURSION_LIMIT)
                 return print_infinite_recursion_bug();
         /*
          * Check this lock's dependency list:
@@ -645,7 +647,7 @@ find_usage_forwards(struct lock_class *source, unsigned int depth)
 
         if (depth > max_recursion_depth)
                 max_recursion_depth = depth;
-        if (depth >= 20)
+        if (depth >= RECURSION_LIMIT)
                 return print_infinite_recursion_bug();
 
         debug_atomic_inc(&nr_find_usage_forwards_checks);
@@ -684,7 +686,7 @@ find_usage_backwards(struct lock_class *source, unsigned int depth)
 
         if (depth > max_recursion_depth)
                 max_recursion_depth = depth;
-        if (depth >= 20)
+        if (depth >= RECURSION_LIMIT)
                 return print_infinite_recursion_bug();
 
         debug_atomic_inc(&nr_find_usage_backwards_checks);
@@ -1079,7 +1081,8 @@ static int static_obj(void *obj)
          */
         for_each_possible_cpu(i) {
                 start = (unsigned long) &__per_cpu_start + per_cpu_offset(i);
-                end   = (unsigned long) &__per_cpu_end   + per_cpu_offset(i);
+                end   = (unsigned long) &__per_cpu_start + PERCPU_ENOUGH_ROOM
+                                        + per_cpu_offset(i);
 
                 if ((addr >= start) && (addr < end))
                         return 1;
@@ -1114,8 +1117,6 @@ 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 +1154,7 @@ 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;
 
@@ -1177,7 +1177,7 @@ 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;
@@ -1249,7 +1249,7 @@ 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);
@@ -1937,7 +1937,7 @@ 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;
@@ -1957,6 +1957,8 @@ 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);
@@ -1995,7 +1997,7 @@ 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;
         }