Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  slab, lockdep: Annotate the locks before using them
  lockdep: Clear whole lockdep_map on initialization
  slab, lockdep: Annotate slab -> rcu -> debug_object -> slab
  lockdep: Fix up warning
  lockdep: Fix trace_hardirqs_on_caller()
  futex: Fix regression with read only mappings

1 files changed, 71 insertions, 21 deletions

diff --git a/mm/slab.c b/mm/slab.c
index 95947400702b..6d90a091fdca 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -622,6 +622,51 @@ int slab_is_available(void)
 static struct lock_class_key on_slab_l3_key;
 static struct lock_class_key on_slab_alc_key;
 
+static struct lock_class_key debugobj_l3_key;
+static struct lock_class_key debugobj_alc_key;
+
+static void slab_set_lock_classes(struct kmem_cache *cachep,
+		struct lock_class_key *l3_key, struct lock_class_key *alc_key,
+		int q)
+{
+	struct array_cache **alc;
+	struct kmem_list3 *l3;
+	int r;
+
+	l3 = cachep->nodelists[q];
+	if (!l3)
+		return;
+
+	lockdep_set_class(&l3->list_lock, l3_key);
+	alc = l3->alien;
+	/*
+	 * FIXME: This check for BAD_ALIEN_MAGIC
+	 * should go away when common slab code is taught to
+	 * work even without alien caches.
+	 * Currently, non NUMA code returns BAD_ALIEN_MAGIC
+	 * for alloc_alien_cache,
+	 */
+	if (!alc || (unsigned long)alc == BAD_ALIEN_MAGIC)
+		return;
+	for_each_node(r) {
+		if (alc[r])
+			lockdep_set_class(&alc[r]->lock, alc_key);
+	}
+}
+
+static void slab_set_debugobj_lock_classes_node(struct kmem_cache *cachep, int node)
+{
+	slab_set_lock_classes(cachep, &debugobj_l3_key, &debugobj_alc_key, node);
+}
+
+static void slab_set_debugobj_lock_classes(struct kmem_cache *cachep)
+{
+	int node;
+
+	for_each_online_node(node)
+		slab_set_debugobj_lock_classes_node(cachep, node);
+}
+
 static void init_node_lock_keys(int q)
 {
 	struct cache_sizes *s = malloc_sizes;
@@ -630,29 +675,14 @@ static void init_node_lock_keys(int q)
 		return;
 
 	for (s = malloc_sizes; s->cs_size != ULONG_MAX; s++) {
-		struct array_cache **alc;
 		struct kmem_list3 *l3;
-		int r;
 
 		l3 = s->cs_cachep->nodelists[q];
 		if (!l3 || OFF_SLAB(s->cs_cachep))
 			continue;
-		lockdep_set_class(&l3->list_lock, &on_slab_l3_key);
-		alc = l3->alien;
-		/*
-		 * FIXME: This check for BAD_ALIEN_MAGIC
-		 * should go away when common slab code is taught to
-		 * work even without alien caches.
-		 * Currently, non NUMA code returns BAD_ALIEN_MAGIC
-		 * for alloc_alien_cache,
-		 */
-		if (!alc || (unsigned long)alc == BAD_ALIEN_MAGIC)
-			continue;
-		for_each_node(r) {
-			if (alc[r])
-				lockdep_set_class(&alc[r]->lock,
-					&on_slab_alc_key);
-		}
+
+		slab_set_lock_classes(s->cs_cachep, &on_slab_l3_key,
+				&on_slab_alc_key, q);
 	}
 }
 
@@ -671,6 +701,14 @@ static void init_node_lock_keys(int q)
 static inline void init_lock_keys(void)
 {
 }
+
+static void slab_set_debugobj_lock_classes_node(struct kmem_cache *cachep, int node)
+{
+}
+
+static void slab_set_debugobj_lock_classes(struct kmem_cache *cachep)
+{
+}
 #endif
 
 /*
@@ -1264,6 +1302,8 @@ static int __cpuinit cpuup_prepare(long cpu)
 		spin_unlock_irq(&l3->list_lock);
 		kfree(shared);
 		free_alien_cache(alien);
+		if (cachep->flags & SLAB_DEBUG_OBJECTS)
+			slab_set_debugobj_lock_classes_node(cachep, node);
 	}
 	init_node_lock_keys(node);
 
@@ -1626,6 +1666,9 @@ void __init kmem_cache_init_late(void)
 {
 	struct kmem_cache *cachep;
 
+	/* Annotate slab for lockdep -- annotate the malloc caches */
+	init_lock_keys();
+
 	/* 6) resize the head arrays to their final sizes */
 	mutex_lock(&cache_chain_mutex);
 	list_for_each_entry(cachep, &cache_chain, next)
@@ -1636,9 +1679,6 @@ void __init kmem_cache_init_late(void)
 	/* Done! */
 	g_cpucache_up = FULL;
 
-	/* Annotate slab for lockdep -- annotate the malloc caches */
-	init_lock_keys();
-
 	/*
 	 * Register a cpu startup notifier callback that initializes
 	 * cpu_cache_get for all new cpus
@@ -2426,6 +2466,16 @@ kmem_cache_create (const char *name, size_t size, size_t align,
 		goto oops;
 	}
 
+	if (flags & SLAB_DEBUG_OBJECTS) {
+		/*
+		 * Would deadlock through slab_destroy()->call_rcu()->
+		 * debug_object_activate()->kmem_cache_alloc().
+		 */
+		WARN_ON_ONCE(flags & SLAB_DESTROY_BY_RCU);
+
+		slab_set_debugobj_lock_classes(cachep);
+	}
+
 	/* cache setup completed, link it into the list */
 	list_add(&cachep->next, &cache_chain);
 oops: