30 files changed, 522 insertions, 395 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index 9a3ec66a9d8..19fad003b19 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -11,8 +11,6 @@ obj-y     = sched.o fork.o exec_domain.o panic.o printk.o \
 	    hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
 	    notifier.o ksysfs.o pm_qos_params.o sched_clock.o
 
-CFLAGS_REMOVE_sched.o = -mno-spe
-
 ifdef CONFIG_FUNCTION_TRACER
 # Do not trace debug files and internal ftrace files
 CFLAGS_REMOVE_lockdep.o = -pg
@@ -21,7 +19,7 @@ CFLAGS_REMOVE_mutex-debug.o = -pg
 CFLAGS_REMOVE_rtmutex-debug.o = -pg
 CFLAGS_REMOVE_cgroup-debug.o = -pg
 CFLAGS_REMOVE_sched_clock.o = -pg
-CFLAGS_REMOVE_sched.o = -mno-spe -pg
+CFLAGS_REMOVE_sched.o = -pg
 endif
 
 obj-$(CONFIG_FREEZER) += freezer.o
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index 8ba0e0d934f..8b509441f49 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -24,6 +24,7 @@ struct audit_chunk {
 	struct list_head trees;		/* with root here */
 	int dead;
 	int count;
+	atomic_long_t refs;
 	struct rcu_head head;
 	struct node {
 		struct list_head list;
@@ -56,7 +57,8 @@ static LIST_HEAD(prune_list);
  * tree is refcounted; one reference for "some rules on rules_list refer to
  * it", one for each chunk with pointer to it.
  *
- * chunk is refcounted by embedded inotify_watch.
+ * chunk is refcounted by embedded inotify_watch + .refs (non-zero refcount
+ * of watch contributes 1 to .refs).
  *
  * node.index allows to get from node.list to containing chunk.
  * MSB of that sucker is stolen to mark taggings that we might have to
@@ -121,6 +123,7 @@ static struct audit_chunk *alloc_chunk(int count)
 	INIT_LIST_HEAD(&chunk->hash);
 	INIT_LIST_HEAD(&chunk->trees);
 	chunk->count = count;
+	atomic_long_set(&chunk->refs, 1);
 	for (i = 0; i < count; i++) {
 		INIT_LIST_HEAD(&chunk->owners[i].list);
 		chunk->owners[i].index = i;
@@ -129,9 +132,8 @@ static struct audit_chunk *alloc_chunk(int count)
 	return chunk;
 }
 
-static void __free_chunk(struct rcu_head *rcu)
+static void free_chunk(struct audit_chunk *chunk)
 {
-	struct audit_chunk *chunk = container_of(rcu, struct audit_chunk, head);
 	int i;
 
 	for (i = 0; i < chunk->count; i++) {
@@ -141,14 +143,16 @@ static void __free_chunk(struct rcu_head *rcu)
 	kfree(chunk);
 }
 
-static inline void free_chunk(struct audit_chunk *chunk)
+void audit_put_chunk(struct audit_chunk *chunk)
 {
-	call_rcu(&chunk->head, __free_chunk);
+	if (atomic_long_dec_and_test(&chunk->refs))
+		free_chunk(chunk);
 }
 
-void audit_put_chunk(struct audit_chunk *chunk)
+static void __put_chunk(struct rcu_head *rcu)
 {
-	put_inotify_watch(&chunk->watch);
+	struct audit_chunk *chunk = container_of(rcu, struct audit_chunk, head);
+	audit_put_chunk(chunk);
 }
 
 enum {HASH_SIZE = 128};
@@ -176,7 +180,7 @@ struct audit_chunk *audit_tree_lookup(const struct inode *inode)
 
 	list_for_each_entry_rcu(p, list, hash) {
 		if (p->watch.inode == inode) {
-			get_inotify_watch(&p->watch);
+			atomic_long_inc(&p->refs);
 			return p;
 		}
 	}
@@ -194,17 +198,49 @@ int audit_tree_match(struct audit_chunk *chunk, struct audit_tree *tree)
 
 /* tagging and untagging inodes with trees */
 
-static void untag_chunk(struct audit_chunk *chunk, struct node *p)
+static struct audit_chunk *find_chunk(struct node *p)
+{
+	int index = p->index & ~(1U<<31);
+	p -= index;
+	return container_of(p, struct audit_chunk, owners[0]);
+}
+
+static void untag_chunk(struct node *p)
 {
+	struct audit_chunk *chunk = find_chunk(p);
 	struct audit_chunk *new;
 	struct audit_tree *owner;
 	int size = chunk->count - 1;
 	int i, j;
 
+	if (!pin_inotify_watch(&chunk->watch)) {
+		/*
+		 * Filesystem is shutting down; all watches are getting
+		 * evicted, just take it off the node list for this
+		 * tree and let the eviction logics take care of the
+		 * rest.
+		 */
+		owner = p->owner;
+		if (owner->root == chunk) {
+			list_del_init(&owner->same_root);
+			owner->root = NULL;
+		}
+		list_del_init(&p->list);
+		p->owner = NULL;
+		put_tree(owner);
+		return;
+	}
+
+	spin_unlock(&hash_lock);
+
+	/*
+	 * pin_inotify_watch() succeeded, so the watch won't go away
+	 * from under us.
+	 */
 	mutex_lock(&chunk->watch.inode->inotify_mutex);
 	if (chunk->dead) {
 		mutex_unlock(&chunk->watch.inode->inotify_mutex);
-		return;
+		goto out;
 	}
 
 	owner = p->owner;
@@ -221,7 +257,7 @@ static void untag_chunk(struct audit_chunk *chunk, struct node *p)
 		inotify_evict_watch(&chunk->watch);
 		mutex_unlock(&chunk->watch.inode->inotify_mutex);
 		put_inotify_watch(&chunk->watch);
-		return;
+		goto out;
 	}
 
 	new = alloc_chunk(size);
@@ -263,7 +299,7 @@ static void untag_chunk(struct audit_chunk *chunk, struct node *p)
 	inotify_evict_watch(&chunk->watch);
 	mutex_unlock(&chunk->watch.inode->inotify_mutex);
 	put_inotify_watch(&chunk->watch);
-	return;
+	goto out;
 
 Fallback:
 	// do the best we can
@@ -277,6 +313,9 @@ Fallback:
 	put_tree(owner);
 	spin_unlock(&hash_lock);
 	mutex_unlock(&chunk->watch.inode->inotify_mutex);
+out:
+	unpin_inotify_watch(&chunk->watch);
+	spin_lock(&hash_lock);
 }
 
 static int create_chunk(struct inode *inode, struct audit_tree *tree)
@@ -387,13 +426,6 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree)
 	return 0;
 }
 
-static struct audit_chunk *find_chunk(struct node *p)
-{
-	int index = p->index & ~(1U<<31);
-	p -= index;
-	return container_of(p, struct audit_chunk, owners[0]);
-}
-
 static void kill_rules(struct audit_tree *tree)
 {
 	struct audit_krule *rule, *next;
@@ -431,17 +463,10 @@ static void prune_one(struct audit_tree *victim)
 	spin_lock(&hash_lock);
 	while (!list_empty(&victim->chunks)) {
 		struct node *p;
-		struct audit_chunk *chunk;
 
 		p = list_entry(victim->chunks.next, struct node, list);
-		chunk = find_chunk(p);
-		get_inotify_watch(&chunk->watch);
-		spin_unlock(&hash_lock);
-
-		untag_chunk(chunk, p);
 
-		put_inotify_watch(&chunk->watch);
-		spin_lock(&hash_lock);
+		untag_chunk(p);
 	}
 	spin_unlock(&hash_lock);
 	put_tree(victim);
@@ -469,7 +494,6 @@ static void trim_marked(struct audit_tree *tree)
 
 	while (!list_empty(&tree->chunks)) {
 		struct node *node;
-		struct audit_chunk *chunk;
 
 		node = list_entry(tree->chunks.next, struct node, list);
 
@@ -477,14 +501,7 @@ static void trim_marked(struct audit_tree *tree)
 		if (!(node->index & (1U<<31)))
 			break;
 
-		chunk = find_chunk(node);
-		get_inotify_watch(&chunk->watch);
-		spin_unlock(&hash_lock);
-
-		untag_chunk(chunk, node);
-
-		put_inotify_watch(&chunk->watch);
-		spin_lock(&hash_lock);
+		untag_chunk(node);
 	}
 	if (!tree->root && !tree->goner) {
 		tree->goner = 1;
@@ -878,7 +895,7 @@ static void handle_event(struct inotify_watch *watch, u32 wd, u32 mask,
 static void destroy_watch(struct inotify_watch *watch)
 {
 	struct audit_chunk *chunk = container_of(watch, struct audit_chunk, watch);
-	free_chunk(chunk);
+	call_rcu(&chunk->head, __put_chunk);
 }
 
 static const struct inotify_operations rtree_inotify_ops = {
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index b7d354e2b0e..9fd85a4640a 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -1094,8 +1094,8 @@ static void audit_inotify_unregister(struct list_head *in_list)
 	list_for_each_entry_safe(p, n, in_list, ilist) {
 		list_del(&p->ilist);
 		inotify_rm_watch(audit_ih, &p->wdata);
-		/* the put matching the get in audit_do_del_rule() */
-		put_inotify_watch(&p->wdata);
+		/* the unpin matching the pin in audit_do_del_rule() */
+		unpin_inotify_watch(&p->wdata);
 	}
 }
 
@@ -1389,9 +1389,13 @@ static inline int audit_del_rule(struct audit_entry *entry,
 				/* Put parent on the inotify un-registration
 				 * list.  Grab a reference before releasing
 				 * audit_filter_mutex, to be released in
-				 * audit_inotify_unregister(). */
-				list_add(&parent->ilist, &inotify_list);
-				get_inotify_watch(&parent->wdata);
+				 * audit_inotify_unregister().
+				 * If filesystem is going away, just leave
+				 * the sucker alone, eviction will take
+				 * care of it.
+				 */
+				if (pin_inotify_watch(&parent->wdata))
+					list_add(&parent->ilist, &inotify_list);
 			}
 		}
 	}
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 358e77564e6..fe00b3b983a 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2039,10 +2039,13 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
 	struct cgroup *cgrp;
 	struct cgroup_iter it;
 	struct task_struct *tsk;
+
 	/*
-	 * Validate dentry by checking the superblock operations
+	 * Validate dentry by checking the superblock operations,
+	 * and make sure it's a directory.
 	 */
-	if (dentry->d_sb->s_op != &cgroup_ops)
+	if (dentry->d_sb->s_op != &cgroup_ops ||
+	    !S_ISDIR(dentry->d_inode->i_mode))
 		 goto err;
 
 	ret = 0;
@@ -2472,10 +2475,7 @@ static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry)
 		mutex_unlock(&cgroup_mutex);
 		return -EBUSY;
 	}
-
-	parent = cgrp->parent;
-	root = cgrp->root;
-	sb = root->sb;
+	mutex_unlock(&cgroup_mutex);
 
 	/*
 	 * Call pre_destroy handlers of subsys. Notify subsystems
@@ -2483,7 +2483,14 @@ static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry)
 	 */
 	cgroup_call_pre_destroy(cgrp);
 
-	if (cgroup_has_css_refs(cgrp)) {
+	mutex_lock(&cgroup_mutex);
+	parent = cgrp->parent;
+	root = cgrp->root;
+	sb = root->sb;
+
+	if (atomic_read(&cgrp->count)
+	    || !list_empty(&cgrp->children)
+	    || cgroup_has_css_refs(cgrp)) {
 		mutex_unlock(&cgroup_mutex);
 		return -EBUSY;
 	}
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
index 7fa476f01d0..fb249e2bcad 100644
--- a/kernel/cgroup_freezer.c
+++ b/kernel/cgroup_freezer.c
@@ -184,9 +184,20 @@ static void freezer_fork(struct cgroup_subsys *ss, struct task_struct *task)
 {
 	struct freezer *freezer;
 
-	task_lock(task);
+	/*
+	 * No lock is needed, since the task isn't on tasklist yet,
+	 * so it can't be moved to another cgroup, which means the
+	 * freezer won't be removed and will be valid during this
+	 * function call.
+	 */
 	freezer = task_freezer(task);
-	task_unlock(task);
+
+	/*
+	 * The root cgroup is non-freezable, so we can skip the
+	 * following check.
+	 */
+	if (!freezer->css.cgroup->parent)
+		return;
 
 	spin_lock_irq(&freezer->lock);
 	BUG_ON(freezer->state == CGROUP_FROZEN);
@@ -331,7 +342,7 @@ static int freezer_write(struct cgroup *cgroup,
 	else if (strcmp(buffer, freezer_state_strs[CGROUP_FROZEN]) == 0)
 		goal_state = CGROUP_FROZEN;
 	else
-		return -EIO;
+		return -EINVAL;
 
 	if (!cgroup_lock_live_group(cgroup))
 		return -ENODEV;
@@ -350,6 +361,8 @@ static struct cftype files[] = {
 
 static int freezer_populate(struct cgroup_subsys *ss, struct cgroup *cgroup)
 {
+	if (!cgroup->parent)
+		return 0;
 	return cgroup_add_files(cgroup, ss, files, ARRAY_SIZE(files));
 }
 
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 3e00526f52e..da7ff6137f3 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -36,6 +36,7 @@
 #include <linux/list.h>
 #include <linux/mempolicy.h>
 #include <linux/mm.h>
+#include <linux/memory.h>
 #include <linux/module.h>
 #include <linux/mount.h>
 #include <linux/namei.h>
@@ -587,7 +588,6 @@ static int generate_sched_domains(cpumask_t **domains,
 	int ndoms;		/* number of sched domains in result */
 	int nslot;		/* next empty doms[] cpumask_t slot */
 
-	ndoms = 0;
 	doms = NULL;
 	dattr = NULL;
 	csa = NULL;
@@ -674,10 +674,8 @@ restart:
 	 * Convert <csn, csa> to <ndoms, doms> and populate cpu masks.
 	 */
 	doms = kmalloc(ndoms * sizeof(cpumask_t), GFP_KERNEL);
-	if (!doms) {
-		ndoms = 0;
+	if (!doms)
 		goto done;
-	}
 
 	/*
 	 * The rest of the code, including the scheduler, can deal with
@@ -732,6 +730,13 @@ restart:
 done:
 	kfree(csa);
 
+	/*
+	 * Fallback to the default domain if kmalloc() failed.
+	 * See comments in partition_sched_domains().
+	 */
+	if (doms == NULL)
+		ndoms = 1;
+
 	*domains    = doms;
 	*attributes = dattr;
 	return ndoms;
@@ -2011,12 +2016,23 @@ static int cpuset_track_online_cpus(struct notifier_block *unused_nb,
  * Call this routine anytime after node_states[N_HIGH_MEMORY] changes.
  * See also the previous routine cpuset_track_online_cpus().
  */
-void cpuset_track_online_nodes(void)
+static int cpuset_track_online_nodes(struct notifier_block *self,
+				unsigned long action, void *arg)
 {
 	cgroup_lock();
-	top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
-	scan_for_empty_cpusets(&top_cpuset);
+	switch (action) {
+	case MEM_ONLINE:
+		top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
+		break;
+	case MEM_OFFLINE:
+		top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
+		scan_for_empty_cpusets(&top_cpuset);
+		break;
+	default:
+		break;
+	}
 	cgroup_unlock();
+	return NOTIFY_OK;
 }
 #endif
 
@@ -2032,6 +2048,7 @@ void __init cpuset_init_smp(void)
 	top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY];
 
 	hotcpu_notifier(cpuset_track_online_cpus, 0);
+	hotplug_memory_notifier(cpuset_track_online_nodes, 10);
 }
 
 /**
diff --git a/kernel/exit.c b/kernel/exit.c
index ae2b92be5fa..30fcdf16737 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -40,7 +40,6 @@
 #include <linux/cn_proc.h>
 #include <linux/mutex.h>
 #include <linux/futex.h>
-#include <linux/compat.h>
 #include <linux/pipe_fs_i.h>
 #include <linux/audit.h> /* for audit_free() */
 #include <linux/resource.h>
@@ -1059,14 +1058,6 @@ NORET_TYPE void do_exit(long code)
 		exit_itimers(tsk->signal);
 	}
 	acct_collect(code, group_dead);
-#ifdef CONFIG_FUTEX
-	if (unlikely(tsk->robust_list))
-		exit_robust_list(tsk);
-#ifdef CONFIG_COMPAT
-	if (unlikely(tsk->compat_robust_list))
-		compat_exit_robust_list(tsk);
-#endif
-#endif
 	if (group_dead)
 		tty_audit_exit();
 	if (unlikely(tsk->audit_context))
@@ -1330,10 +1321,10 @@ static int wait_task_zombie(struct task_struct *p, int options,
 		 * group, which consolidates times for all threads in the
 		 * group including the group leader.
 		 */
+		thread_group_cputime(p, &cputime);
 		spin_lock_irq(&p->parent->sighand->siglock);
 		psig = p->parent->signal;
 		sig = p->signal;
-		thread_group_cputime(p, &cputime);
 		psig->cutime =
 			cputime_add(psig->cutime,
 			cputime_add(cputime.utime,
diff --git a/kernel/extable.c b/kernel/extable.c
index a26cb2e1702..adf0cc9c02d 100644
--- a/kernel/extable.c
+++ b/kernel/extable.c
@@ -66,3 +66,19 @@ int kernel_text_address(unsigned long addr)
 		return 1;
 	return module_text_address(addr) != NULL;
 }
+
+/*
+ * On some architectures (PPC64, IA64) function pointers
+ * are actually only tokens to some data that then holds the
+ * real function address. As a result, to find if a function
+ * pointer is part of the kernel text, we need to do some
+ * special dereferencing first.
+ */
+int func_ptr_is_kernel_text(void *ptr)
+{
+	unsigned long addr;
+	addr = (unsigned long) dereference_function_descriptor(ptr);
+	if (core_kernel_text(addr))
+		return 1;
+	return module_text_address(addr) != NULL;
+}
diff --git a/kernel/fork.c b/kernel/fork.c
index f6083561dfe..2a372a0e206 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -40,6 +40,7 @@
 #include <linux/jiffies.h>
 #include <linux/tracehook.h>
 #include <linux/futex.h>
+#include <linux/compat.h>
 #include <linux/task_io_accounting_ops.h>
 #include <linux/rcupdate.h>
 #include <linux/ptrace.h>
@@ -519,6 +520,16 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
 {
 	struct completion *vfork_done = tsk->vfork_done;
 
+	/* Get rid of any futexes when releasing the mm */
+#ifdef CONFIG_FUTEX
+	if (unlikely(tsk->robust_list))
+		exit_robust_list(tsk);
+#ifdef CONFIG_COMPAT
+	if (unlikely(tsk->compat_robust_list))
+		compat_exit_robust_list(tsk);
+#endif
+#endif
+
 	/* Get rid of any cached register state */
 	deactivate_mm(tsk, mm);
 
diff --git a/kernel/futex.c b/kernel/futex.c
index 8af10027514..e10c5c8786a 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -123,24 +123,6 @@ struct futex_hash_bucket {
 static struct futex_hash_bucket futex_queues[1<<FUTEX_HASHBITS];
 
 /*
- * Take mm->mmap_sem, when futex is shared
- */
-static inline void futex_lock_mm(struct rw_semaphore *fshared)
-{
-	if (fshared)
-		down_read(fshared);
-}
-
-/*
- * Release mm->mmap_sem, when the futex is shared
- */
-static inline void futex_unlock_mm(struct rw_semaphore *fshared)
-{
-	if (fshared)
-		up_read(fshared);
-}
-
-/*
  * We hash on the keys returned from get_futex_key (see below).
  */
 static struct futex_hash_bucket *hash_futex(union futex_key *key)
@@ -161,6 +143,45 @@ static inline int match_futex(union futex_key *key1, union futex_key *key2)
 		&& key1->both.offset == key2->both.offset);
 }
 
+/*
+ * Take a reference to the resource addressed by a key.
+ * Can be called while holding spinlocks.
+ *
+ */
+static void get_futex_key_refs(union futex_key *key)
+{
+	if (!key->both.ptr)
+		return;
+
+	switch (key->both.offset & (FUT_OFF_INODE|FUT_OFF_MMSHARED)) {
+	case FUT_OFF_INODE:
+		atomic_inc(&key->shared.inode->i_count);
+		break;
+	case FUT_OFF_MMSHARED:
+		atomic_inc(&key->private.mm->mm_count);
+		break;
+	}
+}
+
+/*
+ * Drop a reference to the resource addressed by a key.
+ * The hash bucket spinlock must not be held.
+ */
+static void drop_futex_key_refs(union futex_key *key)
+{
+	if (!key->both.ptr)
+		return;
+
+	switch (key->both.offset & (FUT_OFF_INODE|FUT_OFF_MMSHARED)) {
+	case FUT_OFF_INODE:
+		iput(key->shared.inode);
+		break;
+	case FUT_OFF_MMSHARED:
+		mmdrop(key->private.mm);
+		break;
+	}
+}
+
 /**
  * get_futex_key - Get parameters which are the keys for a futex.
  * @uaddr: virtual address of the futex
@@ -179,12 +200,10 @@ static inline int match_futex(union futex_key *key1, union futex_key *key2)
  * For other futexes, it points to &current->mm->mmap_sem and
  * caller must have taken the reader lock. but NOT any spinlocks.
  */
-static int get_futex_key(u32 __user *uaddr, struct rw_semaphore *fshared,
-			 union futex_key *key)
+static int get_futex_key(u32 __user *uaddr, int fshared, union futex_key *key)
 {
 	unsigned long address = (unsigned long)uaddr;
 	struct mm_struct *mm = current->mm;
-	struct vm_area_struct *vma;
 	struct page *page;
 	int err;
 
@@ -208,100 +227,50 @@ static int get_futex_key(u32 __user *uaddr, struct rw_semaphore *fshared,
 			return -EFAULT;
 		key->private.mm = mm;
 		key->private.address = address;
+		get_futex_key_refs(key);
 		return 0;
 	}
-	/*
-	 * The futex is hashed differently depending on whether
-	 * it's in a shared or private mapping.  So check vma first.
-	 */
-	vma = find_extend_vma(mm, address);
-	if (unlikely(!vma))
-		return -EFAULT;
 
-	/*
-	 * Permissions.
-	 */
-	if (unlikely((vma->vm_flags & (VM_IO|VM_READ)) != VM_READ))
-		return (vma->vm_flags & VM_IO) ? -EPERM : -EACCES;
+again:
+	err = get_user_pages_fast(address, 1, 0, &page);
+	if (err < 0)
+		return err;
+
+	lock_page(page);
+	if (!page->mapping) {
+		unlock_page(page);
+		put_page(page);
+		goto again;
+	}
 
 	/*
 	 * Private mappings are handled in a simple way.
 	 *
 	 * NOTE: When userspace waits on a MAP_SHARED mapping, even if
 	 * it's a read-only handle, it's expected that futexes attach to
-	 * the object not the particular process.  Therefore we use
-	 * VM_MAYSHARE here, not VM_SHARED which is restricted to shared
-	 * mappings of _writable_ handles.
+	 * the object not the particular process.
 	 */
-	if (likely(!(vma->vm_flags & VM_MAYSHARE))) {
-		key->both.offset |= FUT_OFF_MMSHARED; /* reference taken on mm */
+	if (PageAnon(page)) {
+		key->both.offset |= FUT_OFF_MMSHARED; /* ref taken on mm */
 		key->private.mm = mm;
 		key->private.address = address;
-		return 0;
+	} else {
+		key->both.offset |= FUT_OFF_INODE; /* inode-based key */
+		key->shared.inode = page->mapping->host;
+		key->shared.pgoff = page->index;
 	}
 
-	/*
-	 * Linear file mappings are also simple.
-	 */
-	key->shared.inode = vma->vm_file->f_path.dentry->d_inode;
-	key->both.offset |= FUT_OFF_INODE; /* inode-based key. */
-	if (likely(!(vma->vm_flags & VM_NONLINEAR))) {
-		key->shared.pgoff = (((address - vma->vm_start) >> PAGE_SHIFT)
-				     + vma->vm_pgoff);
-		return 0;
-	}
+	get_futex_key_refs(key);
 
-	/*
-	 * We could walk the page table to read the non-linear
-	 * pte, and get the page index without fetching the page
-	 * from swap.  But that's a lot of code to duplicate here
-	 * for a rare case, so we simply fetch the page.
-	 */
-	err = get_user_pages(current, mm, address, 1, 0, 0, &page, NULL);
-	if (err >= 0) {
-		key->shared.pgoff =
-			page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
-		put_page(page);
-		return 0;
-	}
-	return err;
-}
-
-/*
- * Take a reference to the resource addressed by a key.
- * Can be called while holding spinlocks.
- *
- */
-static void get_futex_key_refs(union futex_key *key)
-{
-	if (key->both.ptr == NULL)
-		return;
-	switch (key->both.offset & (FUT_OFF_INODE|FUT_OFF_MMSHARED)) {
-		case FUT_OFF_INODE:
-			atomic_inc(&key->shared.inode->i_count);
-			break;
-		case FUT_OFF_MMSHARED:
-			atomic_inc(&key->private.mm->mm_count);
-			break;
-	}
+	unlock_page(page);
+	put_page(page);
+	return 0;
 }
 
-/*
- * Drop a reference to the resource addressed by a key.
- * The hash bucket spinlock must not be held.
- */
-static void drop_futex_key_refs(union futex_key *key)
+static inline
+void put_futex_key(int fshared, union futex_key *key)
 {
-	if (!key->both.ptr)
-		return;
-	switch (key->both.offset & (FUT_OFF_INODE|FUT_OFF_MMSHARED)) {
-		case FUT_OFF_INODE:
-			iput(key->shared.inode);
-			break;
-		case FUT_OFF_MMSHARED:
-			mmdrop(key->private.mm);
-			break;
-	}
+	drop_futex_key_refs(key);
 }
 
 static u32 cmpxchg_futex_value_locked(u32 __user *uaddr, u32 uval, u32 newval)
@@ -328,10 +297,8 @@ static int get_futex_value_locked(u32 *dest, u32 __user *from)
 
 /*
  * Fault handling.
- * if fshared is non NULL, current->mm->mmap_sem is already held
  */
-static int futex_handle_fault(unsigned long address,
-			      struct rw_semaphore *fshared, int attempt)
+static int futex_handle_fault(unsigned long address, int attempt)
 {
 	struct vm_area_struct * vma;
 	struct mm_struct *mm = current->mm;
@@ -340,8 +307,7 @@ static int futex_handle_fault(unsigned long address,
 	if (attempt > 2)
 		return ret;
 
-	if (!fshared)
-		down_read(&mm->mmap_sem);
+	down_read(&mm->mmap_sem);
 	vma = find_vma(mm, address);
 	if (vma && address >= vma->vm_start &&
 	    (vma->vm_flags & VM_WRITE)) {
@@ -361,8 +327,7 @@ static int futex_handle_fault(unsigned long address,
 				current->min_flt++;
 		}
 	}
-	if (!fshared)
-		up_read(&mm->mmap_sem);
+	up_read(&mm->mmap_sem);
 	return ret;
 }
 
@@ -385,6 +350,7 @@ static int refill_pi_state_cache(void)
 	/* pi_mutex gets initialized later */
 	pi_state->owner = NULL;
 	atomic_set(&pi_state->refcount, 1);
+	pi_state->key = FUTEX_KEY_INIT;
 
 	current->pi_state_cache = pi_state;
 
@@ -462,7 +428,7 @@ void exit_pi_state_list(struct task_struct *curr)
 	struct list_head *next, *head = &curr->pi_state_list;
 	struct futex_pi_state *pi_state;
 	struct futex_hash_bucket *hb;
-	union futex_key key;
+	union futex_key key = FUTEX_KEY_INIT;
 
 	if (!futex_cmpxchg_enabled)
 		return;
@@ -719,20 +685,17 @@ double_lock_hb(struct futex_hash_bucket *hb1, struct futex_hash_bucket *hb2)
  * Wake up all waiters hashed on the physical page that is mapped
  * to this virtual address:
  */
-static int futex_wake(u32 __user *uaddr, struct rw_semaphore *fshared,
-		      int nr_wake, u32 bitset)
+static int futex_wake(u32 __user *uaddr, int fshared, int nr_wake, u32 bitset)
 {
 	struct futex_hash_bucket *hb;
 	struct futex_q *this, *next;
 	struct plist_head *head;
-	union futex_key key;
+	union futex_key key = FUTEX_KEY_INIT;
 	int ret;
 
 	if (!bitset)
 		return -EINVAL;
 
-	futex_lock_mm(fshared);
-
 	ret = get_futex_key(uaddr, fshared, &key);
 	if (unlikely(ret != 0))
 		goto out;
@@ -760,7 +723,7 @@ static int futex_wake(u32 __user *uaddr, struct rw_semaphore *fshared,
 
 	spin_unlock(&hb->lock);
 out:
-	futex_unlock_mm(fshared);
+	put_futex_key(fshared, &key);
 	return ret;
 }
 
@@ -769,19 +732,16 @@ out:
  * to this virtual address:
  */
 static int
-futex_wake_op(u32 __user *uaddr1, struct rw_semaphore *fshared,
-	      u32 __user *uaddr2,
+futex_wake_op(u32 __user *uaddr1, int fshared, u32 __user *uaddr2,
 	      int nr_wake, int nr_wake2, int op)
 {
-	union futex_key key1, key2;
+	union futex_key key1 = FUTEX_KEY_INIT, key2 = FUTEX_KEY_INIT;
 	struct futex_hash_bucket *hb1, *hb2;
 	struct plist_head *head;
 	struct futex_q *this, *next;
 	int ret, op_ret, attempt = 0;
 
 retryfull:
-	futex_lock_mm(fshared);
-
 	ret = get_futex_key(uaddr1, fshared, &key1);
 	if (unlikely(ret != 0))
 		goto out;
@@ -826,18 +786,12 @@ retry:
 		 */
 		if (attempt++) {
 			ret = futex_handle_fault((unsigned long)uaddr2,
-						 fshared, attempt);
+						 attempt);
 			if (ret)
 				goto out;
 			goto retry;
 		}
 
-		/*
-		 * If we would have faulted, release mmap_sem,
-		 * fault it in and start all over again.
-		 */
-		futex_unlock_mm(fshared);
-
 		ret = get_user(dummy, uaddr2);
 		if (ret)
 			return ret;
@@ -873,7 +827,8 @@ retry:
 	if (hb1 != hb2)
 		spin_unlock(&hb2->lock);
 out:
-	futex_unlock_mm(fshared);
+	put_futex_key(fshared, &key2);
+	put_futex_key(fshared, &key1);
 
 	return ret;
 }
@@ -882,19 +837,16 @@ out:
  * Requeue all waiters hashed on one physical page to another
  * physical page.
  */
-static int futex_requeue(u32 __user *uaddr1, struct rw_semaphore *fshared,
-			 u32 __user *uaddr2,
+static int futex_requeue(u32 __user *uaddr1, int fshared, u32 __user *uaddr2,
 			 int nr_wake, int nr_requeue, u32 *cmpval)
 {
-	union futex_key key1, key2;
+	union futex_key key1 = FUTEX_KEY_INIT, key2 = FUTEX_KEY_INIT;
 	struct futex_hash_bucket *hb1, *hb2;
 	struct plist_head *head1;
 	struct futex_q *this, *next;
 	int ret, drop_count = 0;
 
  retry:
-	futex_lock_mm(fshared);
-
 	ret = get_futex_key(uaddr1, fshared, &key1);
 	if (unlikely(ret != 0))
 		goto out;
@@ -917,12 +869,6 @@ static int futex_requeue(u32 __user *uaddr1, struct rw_semaphore *fshared,
 			if (hb1 != hb2)
 				spin_unlock(&hb2->lock);
 
-			/*
-			 * If we would have faulted, release mmap_sem, fault
-			 * it in and start all over again.
-			 */
-			futex_unlock_mm(fshared);
-
 			ret = get_user(curval, uaddr1);
 
 			if (!ret)
@@ -974,7 +920,8 @@ out_unlock:
 		drop_futex_key_refs(&key1);
 
 out:
-	futex_unlock_mm(fshared);
+	put_futex_key(fshared, &key2);
+	put_futex_key(fshared, &key1);
 	return ret;
 }
 
@@ -1096,8 +1043,7 @@ static void unqueue_me_pi(struct futex_q *q)
  * private futexes.
  */
 static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
-				struct task_struct *newowner,
-				struct rw_semaphore *fshared)
+				struct task_struct *newowner, int fshared)
 {
 	u32 newtid = task_pid_vnr(newowner) | FUTEX_WAITERS;
 	struct futex_pi_state *pi_state = q->pi_state;
@@ -1176,7 +1122,7 @@ retry:
 handle_fault:
 	spin_unlock(q->lock_ptr);
 
-	ret = futex_handle_fault((unsigned long)uaddr, fshared, attempt++);
+	ret = futex_handle_fault((unsigned long)uaddr, attempt++);
 
 	spin_lock(q->lock_ptr);
 
@@ -1200,7 +1146,7 @@ handle_fault:
 
 static long futex_wait_restart(struct restart_block *restart);
 
-static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared,
+static int futex_wait(u32 __user *uaddr, int fshared,
 		      u32 val, ktime_t *abs_time, u32 bitset)
 {
 	struct task_struct *curr = current;
@@ -1218,8 +1164,7 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared,
 	q.pi_state = NULL;
 	q.bitset = bitset;
  retry:
-	futex_lock_mm(fshared);
-
+	q.key = FUTEX_KEY_INIT;
 	ret = get_futex_key(uaddr, fshared, &q.key);
 	if (unlikely(ret != 0))
 		goto out_release_sem;
@@ -1251,12 +1196,6 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared,
 	if (unlikely(ret)) {
 		queue_unlock(&q, hb);
 
-		/*
-		 * If we would have faulted, release mmap_sem, fault it in and
-		 * start all over again.
-		 */
-		futex_unlock_mm(fshared);
-
 		ret = get_user(uval, uaddr);
 
 		if (!ret)
@@ -1271,12 +1210,6 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared,
 	queue_me(&q, hb);
 
 	/*
-	 * Now the futex is queued and we have checked the data, we
-	 * don't want to hold mmap_sem while we sleep.
-	 */
-	futex_unlock_mm(fshared);
-
-	/*
 	 * There might have been scheduling since the queue_me(), as we
 	 * cannot hold a spinlock across the get_user() in case it
 	 * faults, and we cannot just set TASK_INTERRUPTIBLE state when
@@ -1363,7 +1296,7 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared,
 	queue_unlock(&q, hb);
 
  out_release_sem:
-	futex_unlock_mm(fshared);
+	put_futex_key(fshared, &q.key);
 	return ret;
 }
 
@@ -1371,13 +1304,13 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared,
 static long futex_wait_restart(struct restart_block *restart)
 {
 	u32 __user *uaddr = (u32 __user *)restart->futex.uaddr;
-	struct rw_semaphore *fshared = NULL;
+	int fshared = 0;
 	ktime_t t;
 
 	t.tv64 = restart->futex.time;
 	restart->fn = do_no_restart_syscall;
 	if (restart->futex.flags & FLAGS_SHARED)
-		fshared = &current->mm->mmap_sem;
+		fshared = 1;
 	return (long)futex_wait(uaddr, fshared, restart->futex.val, &t,
 				restart->futex.bitset);
 }
@@ -1389,7 +1322,7 @@ static long futex_wait_restart(struct restart_block *restart)
  * if there are waiters then it will block, it does PI, etc. (Due to
  * races the kernel might see a 0 value of the futex too.)
  */
-static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
+static int futex_lock_pi(u32 __user *uaddr, int fshared,
 			 int detect, ktime_t *time, int trylock)
 {
 	struct hrtimer_sleeper timeout, *to = NULL;
@@ -1412,8 +1345,7 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 
 	q.pi_state = NULL;
  retry:
-	futex_lock_mm(fshared);
-
+	q.key = FUTEX_KEY_INIT;
 	ret = get_futex_key(uaddr, fshared, &q.key);
 	if (unlikely(ret != 0))
 		goto out_release_sem;
@@ -1502,7 +1434,6 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 			 * exit to complete.
 			 */
 			queue_unlock(&q, hb);
-			futex_unlock_mm(fshared);
 			cond_resched();
 			goto retry;
 
@@ -1534,12 +1465,6 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 	 */
 	queue_me(&q, hb);
 
-	/*
-	 * Now the futex is queued and we have checked the data, we
-	 * don't want to hold mmap_sem while we sleep.
-	 */
-	futex_unlock_mm(fshared);
-
 	WARN_ON(!q.pi_state);
 	/*
 	 * Block on the PI mutex:
@@ -1552,7 +1477,6 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 		ret = ret ? 0 : -EWOULDBLOCK;
 	}
 
-	futex_lock_mm(fshared);
 	spin_lock(q.lock_ptr);
 
 	if (!ret) {
@@ -1618,7 +1542,6 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 
 	/* Unqueue and drop the lock */
 	unqueue_me_pi(&q);
-	futex_unlock_mm(fshared);
 
 	if (to)
 		destroy_hrtimer_on_stack(&to->timer);
@@ -1628,7 +1551,7 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 	queue_unlock(&q, hb);
 
  out_release_sem:
-	futex_unlock_mm(fshared);
+	put_futex_key(fshared, &q.key);
 	if (to)
 		destroy_hrtimer_on_stack(&to->timer);
 	return ret;
@@ -1645,15 +1568,12 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
 	queue_unlock(&q, hb);
 
 	if (attempt++) {
-		ret = futex_handle_fault((unsigned long)uaddr, fshared,
-					 attempt);
+		ret = futex_handle_fault((unsigned long)uaddr, attempt);
 		if (ret)
 			goto out_release_sem;
 		goto retry_unlocked;
 	}
 
-	futex_unlock_mm(fshared);
-
 	ret = get_user(uval, uaddr);
 	if (!ret && (uval != -EFAULT))
 		goto retry;
@@ -1668,13 +1588,13 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared,
  * This is the in-kernel slowpath: we look up the PI state (if any),
  * and do the rt-mutex unlock.
  */
-static int futex_unlock_pi(u32 __user *uaddr, struct rw_semaphore *fshared)
+static int futex_unlock_pi(u32 __user *uaddr, int fshared)
 {
 	struct futex_hash_bucket *hb;
 	struct futex_q *this, *next;
 	u32 uval;
 	struct plist_head *head;
-	union futex_key key;
+	union futex_key key = FUTEX_KEY_INIT;
 	int ret, attempt = 0;
 
 retry:
@@ -1685,10 +1605,6 @@ retry:
 	 */
 	if ((uval & FUTEX_TID_MASK) != task_pid_vnr(current))
 		return -EPERM;
-	/*
-	 * First take all the futex related locks:
-	 */
-	futex_lock_mm(fshared);
 
 	ret = get_futex_key(uaddr, fshared, &key);
 	if (unlikely(ret != 0))
@@ -1747,7 +1663,7 @@ retry_unlocked:
 out_unlock:
 	spin_unlock(&hb->lock);
 out:
-	futex_unlock_mm(fshared);
+	put_futex_key(fshared, &key);
 
 	return ret;
 
@@ -1763,16 +1679,13 @@ pi_faulted:
 	spin_unlock(&hb->lock);
 
 	if (attempt++) {
-		ret = futex_handle_fault((unsigned long)uaddr, fshared,
-					 attempt);
+		ret = futex_handle_fault((unsigned long)uaddr, attempt);
 		if (ret)
 			goto out;
 		uval = 0;
 		goto retry_unlocked;
 	}
 
-	futex_unlock_mm(fshared);
-
 	ret = get_user(uval, uaddr);
 	if (!ret && (uval != -EFAULT))
 		goto retry;
@@ -1898,8 +1811,7 @@ retry:
 		 * PI futexes happens in exit_pi_state():
 		 */
 		if (!pi && (uval & FUTEX_WAITERS))
-			futex_wake(uaddr, &curr->mm->mmap_sem, 1,
-				   FUTEX_BITSET_MATCH_ANY);
+			futex_wake(uaddr, 1, 1, FUTEX_BITSET_MATCH_ANY);
 	}
 	return 0;
 }
@@ -1995,10 +1907,10 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
 {
 	int ret = -ENOSYS;
 	int cmd = op & FUTEX_CMD_MASK;
-	struct rw_semaphore *fshared = NULL;
+	int fshared = 0;
 
 	if (!(op & FUTEX_PRIVATE_FLAG))
-		fshared = &current->mm->mmap_sem;
+		fshared = 1;
 
 	switch (cmd) {
 	case FUTEX_WAIT:
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 95d3949f2ae..47e63349d1b 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -664,14 +664,6 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
 
 		/* Timer is expired, act upon the callback mode */
 		switch(timer->cb_mode) {
-		case HRTIMER_CB_IRQSAFE_NO_RESTART:
-			debug_hrtimer_deactivate(timer);
-			/*
-			 * We can call the callback from here. No restart
-			 * happens, so no danger of recursion
-			 */
-			BUG_ON(timer->function(timer) != HRTIMER_NORESTART);
-			return 1;
 		case HRTIMER_CB_IRQSAFE_PERCPU:
 		case HRTIMER_CB_IRQSAFE_UNLOCKED:
 			/*
@@ -683,7 +675,6 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
 			 */
 			debug_hrtimer_deactivate(timer);
 			return 1;
-		case HRTIMER_CB_IRQSAFE:
 		case HRTIMER_CB_SOFTIRQ:
 			/*
 			 * Move everything else into the softirq pending list !
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 5072cf1685a..7b8b0f21a5b 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -304,17 +304,24 @@ int sprint_symbol(char *buffer, unsigned long address)
 	char *modname;
 	const char *name;
 	unsigned long offset, size;
-	char namebuf[KSYM_NAME_LEN];
+	int len;
 
-	name = kallsyms_lookup(address, &size, &offset, &modname, namebuf);
+	name = kallsyms_lookup(address, &size, &offset, &modname, buffer);
 	if (!name)
 		return sprintf(buffer, "0x%lx", address);
 
+	if (name != buffer)
+		strcpy(buffer, name);
+	len = strlen(buffer);
+	buffer += len;
+
 	if (modname)
-		return sprintf(buffer, "%s+%#lx/%#lx [%s]", name, offset,
-				size, modname);
+		len += sprintf(buffer, "+%#lx/%#lx [%s]",
+						offset, size, modname);
 	else
-		return sprintf(buffer, "%s+%#lx/%#lx", name, offset, size);
+		len += sprintf(buffer, "+%#lx/%#lx", offset, size);
+
+	return len;
 }
 
 /* Look up a kernel symbol and print it to the kernel messages. */
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 8b57a2597f2..9f8a3f25259 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -72,7 +72,7 @@ static bool kprobe_enabled;
 DEFINE_MUTEX(kprobe_mutex);		/* Protects kprobe_table */
 static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL;
 static struct {
-	spinlock_t lock ____cacheline_aligned;
+	spinlock_t lock ____cacheline_aligned_in_smp;
 } kretprobe_table_locks[KPROBE_TABLE_SIZE];
 
 static spinlock_t *kretprobe_table_lock_ptr(unsigned long hash)
@@ -613,30 +613,37 @@ static int __kprobes __register_kprobe(struct kprobe *p,
 		return -EINVAL;
 	p->addr = addr;
 
-	if (!kernel_text_address((unsigned long) p->addr) ||
-	    in_kprobes_functions((unsigned long) p->addr))
+	preempt_disable();
+	if (!__kernel_text_address((unsigned long) p->addr) ||
+	    in_kprobes_functions((unsigned long) p->addr)) {
+		preempt_enable();
 		return -EINVAL;
+	}
 
 	p->mod_refcounted = 0;
 
 	/*
 	 * Check if are we probing a module.
 	 */
-	probed_mod = module_text_address((unsigned long) p->addr);
+	probed_mod = __module_text_address((unsigned long) p->addr);
 	if (probed_mod) {
-		struct module *calling_mod = module_text_address(called_from);
+		struct module *calling_mod;
+		calling_mod = __module_text_address(called_from);
 		/*
 		 * We must allow modules to probe themself and in this case
 		 * avoid incrementing the module refcount, so as to allow
 		 * unloading of self probing modules.
 		 */
 		if (calling_mod && calling_mod != probed_mod) {
-			if (unlikely(!try_module_get(probed_mod)))
+			if (unlikely(!try_module_get(probed_mod))) {
+				preempt_enable();
 				return -EINVAL;
+			}
 			p->mod_refcounted = 1;
 		} else
 			probed_mod = NULL;
 	}
+	preempt_enable();
 
 	p->nmissed = 0;
 	INIT_LIST_HEAD(&p->list);
@@ -718,6 +725,10 @@ static void __kprobes __unregister_kprobe_bottom(struct kprobe *p)
 	struct kprobe *old_p;
 
 	if (p->mod_refcounted) {
+		/*
+		 * Since we've already incremented refcount,
+		 * we don't need to disable preemption.
+		 */
 		mod = module_text_address((unsigned long)p->addr);
 		if (mod)
 			module_put(mod);
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index a4285830323..e4bdda8dcf0 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -3285,10 +3285,10 @@ void __init lockdep_info(void)
 {
 	printk("Lock dependency validator: Copyright (c) 2006 Red Hat, Inc., Ingo Molnar\n");
 
-	printk("... MAX_LOCKDEP_SUBCLASSES:    %lu\n", MAX_LOCKDEP_SUBCLASSES);
+	printk("... MAX_LOCKDEP_SUBCLASSES:  %lu\n", MAX_LOCKDEP_SUBCLASSES);
 	printk("... MAX_LOCK_DEPTH:          %lu\n", MAX_LOCK_DEPTH);
 	printk("... MAX_LOCKDEP_KEYS:        %lu\n", MAX_LOCKDEP_KEYS);
-	printk("... CLASSHASH_SIZE:           %lu\n", CLASSHASH_SIZE);
+	printk("... CLASSHASH_SIZE:          %lu\n", CLASSHASH_SIZE);
 	printk("... MAX_LOCKDEP_ENTRIES:     %lu\n", MAX_LOCKDEP_ENTRIES);
 	printk("... MAX_LOCKDEP_CHAINS:      %lu\n", MAX_LOCKDEP_CHAINS);
 	printk("... CHAINHASH_SIZE:          %lu\n", CHAINHASH_SIZE);
diff --git a/kernel/notifier.c b/kernel/notifier.c
index 4282c0a40a5..61d5aa5eced 100644
--- a/kernel/notifier.c
+++ b/kernel/notifier.c
@@ -82,6 +82,14 @@ static int __kprobes notifier_call_chain(struct notifier_block **nl,
 
 	while (nb && nr_to_call) {
 		next_nb = rcu_dereference(nb->next);
+
+#ifdef CONFIG_DEBUG_NOTIFIERS
+		if (unlikely(!func_ptr_is_kernel_text(nb->notifier_call))) {
+			WARN(1, "Invalid notifier called!");
+			nb = next_nb;
+			continue;
+		}
+#endif
 		ret = nb->notifier_call(nb, val, v);
 
 		if (nr_calls)
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 153dcb2639c..3f4377e0aa0 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -58,21 +58,21 @@ void thread_group_cputime(
 	struct task_struct *tsk,
 	struct task_cputime *times)
 {
-	struct signal_struct *sig;
+	struct task_cputime *totals, *tot;
 	int i;
-	struct task_cputime *tot;
 
-	sig = tsk->signal;
-	if (unlikely(!sig) || !sig->cputime.totals) {
+	totals = tsk->signal->cputime.totals;
+	if (!totals) {
 		times->utime = tsk->utime;
 		times->stime = tsk->stime;
 		times->sum_exec_runtime = tsk->se.sum_exec_runtime;
 		return;
 	}
+
 	times->stime = times->utime = cputime_zero;
 	times->sum_exec_runtime = 0;
 	for_each_possible_cpu(i) {
-		tot = per_cpu_ptr(tsk->signal->cputime.totals, i);
+		tot = per_cpu_ptr(totals, i);
 		times->utime = cputime_add(times->utime, tot->utime);
 		times->stime = cputime_add(times->stime, tot->stime);
 		times->sum_exec_runtime += tot->sum_exec_runtime;
@@ -1308,9 +1308,10 @@ static inline int task_cputime_expired(const struct task_cputime *sample,
  */
 static inline int fastpath_timer_check(struct task_struct *tsk)
 {
-	struct signal_struct *sig = tsk->signal;
+	struct signal_struct *sig;
 
-	if (unlikely(!sig))
+	/* tsk == current, ensure it is safe to use ->signal/sighand */
+	if (unlikely(tsk->exit_state))
 		return 0;
 
 	if (!task_cputime_zero(&tsk->cputime_expires)) {
@@ -1323,6 +1324,8 @@ static inline int fastpath_timer_check(struct task_struct *tsk)
 		if (task_cputime_expired(&task_sample, &tsk->cputime_expires))
 			return 1;
 	}
+
+	sig = tsk->signal;
 	if (!task_cputime_zero(&sig->cputime_expires)) {
 		struct task_cputime group_sample;
 
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 19122cf6d82..b8f7ce9473e 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -174,7 +174,7 @@ static void suspend_test_finish(const char *label)
 	 * has some performance issues.  The stack dump of a WARN_ON
 	 * is more likely to get the right attention than a printk...
 	 */
-	WARN_ON(msec > (TEST_SUSPEND_SECONDS * 1000));
+	WARN(msec > (TEST_SUSPEND_SECONDS * 1000), "Component: %s\n", label);
 }
 
 #else
diff --git a/kernel/profile.c b/kernel/profile.c
index 9830a037d8d..5b7d1ac7124 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -544,7 +544,7 @@ static const struct file_operations proc_profile_operations = {
 };
 
 #ifdef CONFIG_SMP
-static void __init profile_nop(void *unused)
+static inline void profile_nop(void *unused)
 {
 }
 
diff --git a/kernel/rcuclassic.c b/kernel/rcuclassic.c
index 37f72e55154..e503a002f33 100644
--- a/kernel/rcuclassic.c
+++ b/kernel/rcuclassic.c
@@ -191,7 +191,7 @@ static void print_other_cpu_stall(struct rcu_ctrlblk *rcp)
 
 	/* OK, time to rat on our buddy... */
 
-	printk(KERN_ERR "RCU detected CPU stalls:");
+	printk(KERN_ERR "INFO: RCU detected CPU stalls:");
 	for_each_possible_cpu(cpu) {
 		if (cpu_isset(cpu, rcp->cpumask))
 			printk(" %d", cpu);
@@ -204,7 +204,7 @@ static void print_cpu_stall(struct rcu_ctrlblk *rcp)
 {
 	unsigned long flags;
 
-	printk(KERN_ERR "RCU detected CPU %d stall (t=%lu/%lu jiffies)\n",
+	printk(KERN_ERR "INFO: RCU detected CPU %d stall (t=%lu/%lu jiffies)\n",
 			smp_processor_id(), jiffies,
 			jiffies - rcp->gp_start);
 	dump_stack();
diff --git a/kernel/relay.c b/kernel/relay.c
index 8d13a7855c0..32b0befdcb6 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -400,7 +400,7 @@ void relay_reset(struct rchan *chan)
 	}
 
 	mutex_lock(&relay_channels_mutex);
-	for_each_online_cpu(i)
+	for_each_possible_cpu(i)
 		if (chan->buf[i])
 			__relay_reset(chan->buf[i], 0);
 	mutex_unlock(&relay_channels_mutex);
@@ -611,10 +611,9 @@ struct rchan *relay_open(const char *base_filename,
 	return chan;
 
 free_bufs:
-	for_each_online_cpu(i) {
-		if (!chan->buf[i])
-			break;
-		relay_close_buf(chan->buf[i]);
+	for_each_possible_cpu(i) {
+		if (chan->buf[i])
+			relay_close_buf(chan->buf[i]);
 	}
 
 	kref_put(&chan->kref, relay_destroy_channel);
diff --git a/kernel/sched.c b/kernel/sched.c
index 2a106b6b78b..558e5f28426 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -1456,6 +1456,8 @@ static unsigned long cpu_avg_load_per_task(int cpu)
 
 	if (rq->nr_running)
 		rq->avg_load_per_task = rq->load.weight / rq->nr_running;
+	else
+		rq->avg_load_per_task = 0;
 
 	return rq->avg_load_per_task;
 }
@@ -4200,7 +4202,6 @@ void account_steal_time(struct task_struct *p, cputime_t steal)
 
 	if (p == rq->idle) {
 		p->stime = cputime_add(p->stime, steal);
-		account_group_system_time(p, steal);
 		if (atomic_read(&rq->nr_iowait) > 0)
 			cpustat->iowait = cputime64_add(cpustat->iowait, tmp);
 		else
@@ -5868,6 +5869,8 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
 	struct rq *rq = cpu_rq(cpu);
 	unsigned long flags;
 
+	spin_lock_irqsave(&rq->lock, flags);
+
 	__sched_fork(idle);
 	idle->se.exec_start = sched_clock();
 
@@ -5875,7 +5878,6 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
 	idle->cpus_allowed = cpumask_of_cpu(cpu);
 	__set_task_cpu(idle, cpu);
 
-	spin_lock_irqsave(&rq->lock, flags);
 	rq->curr = rq->idle = idle;
 #if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
 	idle->oncpu = 1;
@@ -7786,13 +7788,14 @@ static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur,
  *
  * The passed in 'doms_new' should be kmalloc'd. This routine takes
  * ownership of it and will kfree it when done with it. If the caller
- * failed the kmalloc call, then it can pass in doms_new == NULL,
- * and partition_sched_domains() will fallback to the single partition
- * 'fallback_doms', it also forces the domains to be rebuilt.
+ * failed the kmalloc call, then it can pass in doms_new == NULL &&
+ * ndoms_new == 1, and partition_sched_domains() will fallback to
+ * the single partition 'fallback_doms', it also forces the domains
+ * to be rebuilt.
  *
- * If doms_new==NULL it will be replaced with cpu_online_map.
- * ndoms_new==0 is a special case for destroying existing domains.
- * It will not create the default domain.
+ * If doms_new == NULL it will be replaced with cpu_online_map.
+ * ndoms_new == 0 is a special case for destroying existing domains,
+ * and it will not create the default domain.
  *
  * Call with hotplug lock held
  */
diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index 48ecc51e770..26ed8e3d1c1 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -423,10 +423,11 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 #undef __P
 
 	{
+		unsigned int this_cpu = raw_smp_processor_id();
 		u64 t0, t1;
 
-		t0 = sched_clock();
-		t1 = sched_clock();
+		t0 = cpu_clock(this_cpu);
+		t1 = cpu_clock(this_cpu);
 		SEQ_printf(m, "%-35s:%21Ld\n",
 			   "clock-delta", (long long)(t1-t0));
 	}
diff --git a/kernel/sched_stats.h b/kernel/sched_stats.h
index ee71bec1da6..7dbf72a2b02 100644
--- a/kernel/sched_stats.h
+++ b/kernel/sched_stats.h
@@ -298,9 +298,11 @@ static inline void account_group_user_time(struct task_struct *tsk,
 {
 	struct signal_struct *sig;
 
-	sig = tsk->signal;
-	if (unlikely(!sig))
+	/* tsk == current, ensure it is safe to use ->signal */
+	if (unlikely(tsk->exit_state))
 		return;
+
+	sig = tsk->signal;
 	if (sig->cputime.totals) {
 		struct task_cputime *times;
 
@@ -325,9 +327,11 @@ static inline void account_group_system_time(struct task_struct *tsk,
 {
 	struct signal_struct *sig;
 
-	sig = tsk->signal;
-	if (unlikely(!sig))
+	/* tsk == current, ensure it is safe to use ->signal */
+	if (unlikely(tsk->exit_state))
 		return;
+
+	sig = tsk->signal;
 	if (sig->cputime.totals) {
 		struct task_cputime *times;
 
@@ -353,8 +357,11 @@ static inline void account_group_exec_runtime(struct task_struct *tsk,
 	struct signal_struct *sig;
 
 	sig = tsk->signal;
+	/* see __exit_signal()->task_rq_unlock_wait() */
+	barrier();
 	if (unlikely(!sig))
 		return;
+
 	if (sig->cputime.totals) {
 		struct task_cputime *times;
 
diff --git a/kernel/softlockup.c b/kernel/softlockup.c
index 3953e4aed73..884e6cd2769 100644
--- a/kernel/softlockup.c
+++ b/kernel/softlockup.c
@@ -164,7 +164,7 @@ unsigned long __read_mostly sysctl_hung_task_check_count = 1024;
 /*
  * Zero means infinite timeout - no checking done:
  */
-unsigned long __read_mostly sysctl_hung_task_timeout_secs = 120;
+unsigned long __read_mostly sysctl_hung_task_timeout_secs = 480;
 
 unsigned long __read_mostly sysctl_hung_task_warnings = 10;
 
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index 9bc4c00872c..24e8ceacc38 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -112,7 +112,7 @@ static int chill(void *unused)
 int __stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus)
 {
 	struct work_struct *sm_work;
-	int i;
+	int i, ret;
 
 	/* Set up initial state. */
 	mutex_lock(&lock);
@@ -137,8 +137,9 @@ int __stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus)
 	/* This will release the thread on our CPU. */
 	put_cpu();
 	flush_workqueue(stop_machine_wq);
+	ret = active.fnret;
 	mutex_unlock(&lock);
-	return active.fnret;
+	return ret;
 }
 
 int stop_machine(int (*fn)(void *), void *data, const cpumask_t *cpus)
diff --git a/kernel/sys.c b/kernel/sys.c
index 31deba8f7d1..5fc3a0cfb99 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -858,8 +858,8 @@ void do_sys_times(struct tms *tms)
 	struct task_cputime cputime;
 	cputime_t cutime, cstime;
 
-	spin_lock_irq(&current->sighand->siglock);
 	thread_group_cputime(current, &cputime);
+	spin_lock_irq(&current->sighand->siglock);
 	cutime = current->signal->cutime;
 	cstime = current->signal->cstime;
 	spin_unlock_irq(&current->sighand->siglock);
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index a77b27b11b0..e14a2328170 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -31,7 +31,7 @@ cond_syscall(sys_socketpair);
 cond_syscall(sys_bind);
 cond_syscall(sys_listen);
 cond_syscall(sys_accept);
-cond_syscall(sys_paccept);
+cond_syscall(sys_accept4);
 cond_syscall(sys_connect);
 cond_syscall(sys_getsockname);
 cond_syscall(sys_getpeername);
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 4a39d24568c..78db083390f 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -185,7 +185,6 @@ enum {
 };
 
 static int ftrace_filtered;
-static int tracing_on;
 
 static LIST_HEAD(ftrace_new_addrs);
 
@@ -327,96 +326,89 @@ ftrace_record_ip(unsigned long ip)
 
 static int
 __ftrace_replace_code(struct dyn_ftrace *rec,
-		      unsigned char *old, unsigned char *new, int enable)
+		      unsigned char *nop, int enable)
 {
 	unsigned long ip, fl;
+	unsigned char *call, *old, *new;
 
 	ip = rec->ip;
 
-	if (ftrace_filtered && enable) {
+	/*
+	 * If this record is not to be traced and
+	 * it is not enabled then do nothing.
+	 *
+	 * If this record is not to be traced and
+	 * it is enabled then disabled it.
+	 *
+	 */
+	if (rec->flags & FTRACE_FL_NOTRACE) {
+		if (rec->flags & FTRACE_FL_ENABLED)
+			rec->flags &= ~FTRACE_FL_ENABLED;
+		else
+			return 0;
+
+	} else if (ftrace_filtered && enable) {
 		/*
-		 * If filtering is on:
-		 *
-		 * If this record is set to be filtered and
-		 * is enabled then do nothing.
-		 *
-		 * If this record is set to be filtered and
-		 * it is not enabled, enable it.
-		 *
-		 * If this record is not set to be filtered
-		 * and it is not enabled do nothing.
-		 *
-		 * If this record is set not to trace then
-		 * do nothing.
-		 *
-		 * If this record is set not to trace and
-		 * it is enabled then disable it.
-		 *
-		 * If this record is not set to be filtered and
-		 * it is enabled, disable it.
+		 * Filtering is on:
 		 */
 
-		fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_NOTRACE |
-				   FTRACE_FL_ENABLED);
+		fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED);
 
-		if ((fl ==  (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) ||
-		    (fl ==  (FTRACE_FL_FILTER | FTRACE_FL_NOTRACE)) ||
-		    !fl || (fl == FTRACE_FL_NOTRACE))
+		/* Record is filtered and enabled, do nothing */
+		if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED))
 			return 0;
 
-		/*
-		 * If it is enabled disable it,
-		 * otherwise enable it!
-		 */
-		if (fl & FTRACE_FL_ENABLED) {
-			/* swap new and old */
-			new = old;
-			old = ftrace_call_replace(ip, FTRACE_ADDR);
+		/* Record is not filtered and is not enabled do nothing */
+		if (!fl)
+			return 0;
+
+		/* Record is not filtered but enabled, disable it */
+		if (fl == FTRACE_FL_ENABLED)
 			rec->flags &= ~FTRACE_FL_ENABLED;
-		} else {
-			new = ftrace_call_replace(ip, FTRACE_ADDR);
+		else
+		/* Otherwise record is filtered but not enabled, enable it */
 			rec->flags |= FTRACE_FL_ENABLED;
-		}
 	} else {
+		/* Disable or not filtered */
 
 		if (enable) {
-			/*
-			 * If this record is set not to trace and is
-			 * not enabled, do nothing.
-			 */
-			fl = rec->flags & (FTRACE_FL_NOTRACE | FTRACE_FL_ENABLED);
-			if (fl == FTRACE_FL_NOTRACE)
-				return 0;
-
-			new = ftrace_call_replace(ip, FTRACE_ADDR);
-		} else
-			old = ftrace_call_replace(ip, FTRACE_ADDR);
-
-		if (enable) {
+			/* if record is enabled, do nothing */
 			if (rec->flags & FTRACE_FL_ENABLED)
 				return 0;
+
 			rec->flags |= FTRACE_FL_ENABLED;
+
 		} else {
+
+			/* if record is not enabled do nothing */
 			if (!(rec->flags & FTRACE_FL_ENABLED))
 				return 0;
+
 			rec->flags &= ~FTRACE_FL_ENABLED;
 		}
 	}
 
+	call = ftrace_call_replace(ip, FTRACE_ADDR);
+
+	if (rec->flags & FTRACE_FL_ENABLED) {
+		old = nop;
+		new = call;
+	} else {
+		old = call;
+		new = nop;
+	}
+
 	return ftrace_modify_code(ip, old, new);
 }
 
 static void ftrace_replace_code(int enable)
 {
 	int i, failed;
-	unsigned char *new = NULL, *old = NULL;
+	unsigned char *nop = NULL;
 	struct dyn_ftrace *rec;
 	struct ftrace_page *pg;
 
-	if (enable)
-		old = ftrace_nop_replace();
-	else
-		new = ftrace_nop_replace();
+	nop = ftrace_nop_replace();
 
 	for (pg = ftrace_pages_start; pg; pg = pg->next) {
 		for (i = 0; i < pg->index; i++) {
@@ -434,7 +426,7 @@ static void ftrace_replace_code(int enable)
 				unfreeze_record(rec);
 			}
 
-			failed = __ftrace_replace_code(rec, old, new, enable);
+			failed = __ftrace_replace_code(rec, nop, enable);
 			if (failed && (rec->flags & FTRACE_FL_CONVERTED)) {
 				rec->flags |= FTRACE_FL_FAILED;
 				if ((system_state == SYSTEM_BOOTING) ||
@@ -506,13 +498,10 @@ static int __ftrace_modify_code(void *data)
 {
 	int *command = data;
 
-	if (*command & FTRACE_ENABLE_CALLS) {
+	if (*command & FTRACE_ENABLE_CALLS)
 		ftrace_replace_code(1);
-		tracing_on = 1;
-	} else if (*command & FTRACE_DISABLE_CALLS) {
+	else if (*command & FTRACE_DISABLE_CALLS)
 		ftrace_replace_code(0);
-		tracing_on = 0;
-	}
 
 	if (*command & FTRACE_UPDATE_TRACE_FUNC)
 		ftrace_update_ftrace_func(ftrace_trace_function);
@@ -538,8 +527,7 @@ static void ftrace_startup(void)
 
 	mutex_lock(&ftrace_start_lock);
 	ftrace_start++;
-	if (ftrace_start == 1)
-		command |= FTRACE_ENABLE_CALLS;
+	command |= FTRACE_ENABLE_CALLS;
 
 	if (saved_ftrace_func != ftrace_trace_function) {
 		saved_ftrace_func = ftrace_trace_function;
@@ -677,7 +665,7 @@ static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
 
 	cnt = num_to_init / ENTRIES_PER_PAGE;
 	pr_info("ftrace: allocating %ld entries in %d pages\n",
-		num_to_init, cnt);
+		num_to_init, cnt + 1);
 
 	for (i = 0; i < cnt; i++) {
 		pg->next = (void *)get_zeroed_page(GFP_KERNEL);
@@ -738,6 +726,9 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
 		    ((iter->flags & FTRACE_ITER_FAILURES) &&
 		     !(rec->flags & FTRACE_FL_FAILED)) ||
 
+		    ((iter->flags & FTRACE_ITER_FILTER) &&
+		     !(rec->flags & FTRACE_FL_FILTER)) ||
+
 		    ((iter->flags & FTRACE_ITER_NOTRACE) &&
 		     !(rec->flags & FTRACE_FL_NOTRACE))) {
 			rec = NULL;
@@ -757,13 +748,11 @@ static void *t_start(struct seq_file *m, loff_t *pos)
 	void *p = NULL;
 	loff_t l = -1;
 
-	if (*pos != iter->pos) {
-		for (p = t_next(m, p, &l); p && l < *pos; p = t_next(m, p, &l))
-			;
-	} else {
-		l = *pos;
-		p = t_next(m, p, &l);
-	}
+	if (*pos > iter->pos)
+		*pos = iter->pos;
+
+	l = *pos;
+	p = t_next(m, p, &l);
 
 	return p;
 }
@@ -774,15 +763,21 @@ static void t_stop(struct seq_file *m, void *p)
 
 static int t_show(struct seq_file *m, void *v)
 {
+	struct ftrace_iterator *iter = m->private;
 	struct dyn_ftrace *rec = v;
 	char str[KSYM_SYMBOL_LEN];
+	int ret = 0;
 
 	if (!rec)
 		return 0;
 
 	kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
 
-	seq_printf(m, "%s\n", str);
+	ret = seq_printf(m, "%s\n", str);
+	if (ret < 0) {
+		iter->pos--;
+		iter->idx--;
+	}
 
 	return 0;
 }
@@ -808,7 +803,7 @@ ftrace_avail_open(struct inode *inode, struct file *file)
 		return -ENOMEM;
 
 	iter->pg = ftrace_pages_start;
-	iter->pos = -1;
+	iter->pos = 0;
 
 	ret = seq_open(file, &show_ftrace_seq_ops);
 	if (!ret) {
@@ -895,7 +890,7 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
 
 	if (file->f_mode & FMODE_READ) {
 		iter->pg = ftrace_pages_start;
-		iter->pos = -1;
+		iter->pos = 0;
 		iter->flags = enable ? FTRACE_ITER_FILTER :
 			FTRACE_ITER_NOTRACE;
 
@@ -1186,7 +1181,7 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
 
 	mutex_lock(&ftrace_sysctl_lock);
 	mutex_lock(&ftrace_start_lock);
-	if (iter->filtered && ftrace_start && ftrace_enabled)
+	if (ftrace_start && ftrace_enabled)
 		ftrace_run_update_code(FTRACE_ENABLE_CALLS);
 	mutex_unlock(&ftrace_start_lock);
 	mutex_unlock(&ftrace_sysctl_lock);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 2f76193c348..f780e9552f9 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -16,14 +16,49 @@
 #include <linux/list.h>
 #include <linux/fs.h>
 
+#include "trace.h"
+
+/* Global flag to disable all recording to ring buffers */
+static int ring_buffers_off __read_mostly;
+
+/**
+ * tracing_on - enable all tracing buffers
+ *
+ * This function enables all tracing buffers that may have been
+ * disabled with tracing_off.
+ */
+void tracing_on(void)
+{
+	ring_buffers_off = 0;
+}
+
+/**
+ * tracing_off - turn off all tracing buffers
+ *
+ * This function stops all tracing buffers from recording data.
+ * It does not disable any overhead the tracers themselves may
+ * be causing. This function simply causes all recording to
+ * the ring buffers to fail.
+ */
+void tracing_off(void)
+{
+	ring_buffers_off = 1;
+}
+
 /* Up this if you want to test the TIME_EXTENTS and normalization */
 #define DEBUG_SHIFT 0
 
 /* FIXME!!! */
 u64 ring_buffer_time_stamp(int cpu)
 {
+	u64 time;
+
+	preempt_disable_notrace();
 	/* shift to debug/test normalization and TIME_EXTENTS */
-	return sched_clock() << DEBUG_SHIFT;
+	time = sched_clock() << DEBUG_SHIFT;
+	preempt_enable_notrace();
+
+	return time;
 }
 
 void ring_buffer_normalize_time_stamp(int cpu, u64 *ts)
@@ -503,6 +538,12 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size)
 	LIST_HEAD(pages);
 	int i, cpu;
 
+	/*
+	 * Always succeed at resizing a non-existent buffer:
+	 */
+	if (!buffer)
+		return size;
+
 	size = DIV_ROUND_UP(size, BUF_PAGE_SIZE);
 	size *= BUF_PAGE_SIZE;
 	buffer_size = buffer->pages * BUF_PAGE_SIZE;
@@ -576,6 +617,7 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size)
 		list_del_init(&page->list);
 		free_buffer_page(page);
 	}
+	mutex_unlock(&buffer->mutex);
 	return -ENOMEM;
 }
 
@@ -1133,6 +1175,9 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer,
 	struct ring_buffer_event *event;
 	int cpu, resched;
 
+	if (ring_buffers_off)
+		return NULL;
+
 	if (atomic_read(&buffer->record_disabled))
 		return NULL;
 
@@ -1249,6 +1294,9 @@ int ring_buffer_write(struct ring_buffer *buffer,
 	int ret = -EBUSY;
 	int cpu, resched;
 
+	if (ring_buffers_off)
+		return -EBUSY;
+
 	if (atomic_read(&buffer->record_disabled))
 		return -EBUSY;
 
@@ -2070,3 +2118,69 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
 	return 0;
 }
 
+static ssize_t
+rb_simple_read(struct file *filp, char __user *ubuf,
+	       size_t cnt, loff_t *ppos)
+{
+	int *p = filp->private_data;
+	char buf[64];
+	int r;
+
+	/* !ring_buffers_off == tracing_on */
+	r = sprintf(buf, "%d\n", !*p);
+
+	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+rb_simple_write(struct file *filp, const char __user *ubuf,
+		size_t cnt, loff_t *ppos)
+{
+	int *p = filp->private_data;
+	char buf[64];
+	long val;
+	int ret;
+
+	if (cnt >= sizeof(buf))
+		return -EINVAL;
+
+	if (copy_from_user(&buf, ubuf, cnt))
+		return -EFAULT;
+
+	buf[cnt] = 0;
+
+	ret = strict_strtoul(buf, 10, &val);
+	if (ret < 0)
+		return ret;
+
+	/* !ring_buffers_off == tracing_on */
+	*p = !val;
+
+	(*ppos)++;
+
+	return cnt;
+}
+
+static struct file_operations rb_simple_fops = {
+	.open		= tracing_open_generic,
+	.read		= rb_simple_read,
+	.write		= rb_simple_write,
+};
+
+
+static __init int rb_init_debugfs(void)
+{
+	struct dentry *d_tracer;
+	struct dentry *entry;
+
+	d_tracer = tracing_init_dentry();
+
+	entry = debugfs_create_file("tracing_on", 0644, d_tracer,
+				    &ring_buffers_off, &rb_simple_fops);
+	if (!entry)
+		pr_warning("Could not create debugfs 'tracing_on' entry\n");
+
+	return 0;
+}
+
+fs_initcall(rb_init_debugfs);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 697eda36b86..d86e3252f30 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1936,6 +1936,7 @@ __tracing_open(struct inode *inode, struct file *file, int *ret)
 			ring_buffer_read_finish(iter->buffer_iter[cpu]);
 	}
 	mutex_unlock(&trace_types_lock);
+	kfree(iter);
 
 	return ERR_PTR(-ENOMEM);
 }