1 files changed, 23 insertions, 13 deletions

diff --git a/kernel/futex.c b/kernel/futex.c
index 6c91f938005d..1dc98e4dd287 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -607,6 +607,22 @@ static int unlock_futex_pi(u32 __user *uaddr, u32 uval)
 }
 
 /*
+ * Express the locking dependencies for lockdep:
+ */
+static inline void
+double_lock_hb(struct futex_hash_bucket *hb1, struct futex_hash_bucket *hb2)
+{
+        if (hb1 <= hb2) {
+                spin_lock(&hb1->lock);
+                if (hb1 < hb2)
+                        spin_lock_nested(&hb2->lock, SINGLE_DEPTH_NESTING);
+        } else { /* hb1 > hb2 */
+                spin_lock(&hb2->lock);
+                spin_lock_nested(&hb1->lock, SINGLE_DEPTH_NESTING);
+        }
+}
+
+/*
  * Wake up all waiters hashed on the physical page that is mapped
  * to this virtual address:
  */
@@ -630,8 +646,10 @@ static int futex_wake(u32 __user *uaddr, int nr_wake)
 
         list_for_each_entry_safe(this, next, head, list) {
                 if (match_futex (&this->key, &key)) {
-                        if (this->pi_state)
-                                return -EINVAL;
+                        if (this->pi_state) {
+                                ret = -EINVAL;
+                                break;
+                        }
                         wake_futex(this);
                         if (++ret >= nr_wake)
                                 break;
@@ -672,11 +690,7 @@ retryfull:
         hb2 = hash_futex(&key2);
 
 retry:
-        if (hb1 < hb2)
-                spin_lock(&hb1->lock);
-        spin_lock(&hb2->lock);
-        if (hb1 > hb2)
-                spin_lock(&hb1->lock);
+        double_lock_hb(hb1, hb2);
 
         op_ret = futex_atomic_op_inuser(op, uaddr2);
         if (unlikely(op_ret < 0)) {
@@ -785,11 +799,7 @@ static int futex_requeue(u32 __user *uaddr1, u32 __user *uaddr2,
         hb1 = hash_futex(&key1);
         hb2 = hash_futex(&key2);
 
-        if (hb1 < hb2)
-                spin_lock(&hb1->lock);
-        spin_lock(&hb2->lock);
-        if (hb1 > hb2)
-                spin_lock(&hb1->lock);
+        double_lock_hb(hb1, hb2);
 
         if (likely(cmpval != NULL)) {
                 u32 curval;
@@ -1208,7 +1218,7 @@ static int do_futex_lock_pi(u32 __user *uaddr, int detect, int trylock,
         }
 
         down_read(&curr->mm->mmap_sem);
-        hb = queue_lock(&q, -1, NULL);
+        spin_lock(q.lock_ptr);
 
         /*
          * Got the lock. We might not be the anticipated owner if we