Back-merge tag 'v4.7-rc5' into drm-next

Linux 4.7-rc5

The fsl-dcu pull needs -rc3 so go to -rc5 for now.

1 files changed, 9 insertions, 6 deletions

diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index e364b424b019..a70b90db3909 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -486,9 +486,6 @@ __ww_mutex_lock_check_stamp(struct mutex *lock, struct ww_acquire_ctx *ctx)
 	if (!hold_ctx)
 		return 0;
 
-	if (unlikely(ctx == hold_ctx))
-		return -EALREADY;
-
 	if (ctx->stamp - hold_ctx->stamp <= LONG_MAX &&
 	    (ctx->stamp != hold_ctx->stamp || ctx > hold_ctx)) {
 #ifdef CONFIG_DEBUG_MUTEXES
@@ -514,6 +511,12 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 	unsigned long flags;
 	int ret;
 
+	if (use_ww_ctx) {
+		struct ww_mutex *ww = container_of(lock, struct ww_mutex, base);
+		if (unlikely(ww_ctx == READ_ONCE(ww->ctx)))
+			return -EALREADY;
+	}
+
 	preempt_disable();
 	mutex_acquire_nest(&lock->dep_map, subclass, 0, nest_lock, ip);
 
@@ -534,7 +537,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 		goto skip_wait;
 
 	debug_mutex_lock_common(lock, &waiter);
-	debug_mutex_add_waiter(lock, &waiter, task_thread_info(task));
+	debug_mutex_add_waiter(lock, &waiter, task);
 
 	/* add waiting tasks to the end of the waitqueue (FIFO): */
 	list_add_tail(&waiter.list, &lock->wait_list);
@@ -581,7 +584,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 	}
 	__set_task_state(task, TASK_RUNNING);
 
-	mutex_remove_waiter(lock, &waiter, current_thread_info());
+	mutex_remove_waiter(lock, &waiter, task);
 	/* set it to 0 if there are no waiters left: */
 	if (likely(list_empty(&lock->wait_list)))
 		atomic_set(&lock->count, 0);
@@ -602,7 +605,7 @@ skip_wait:
 	return 0;
 
 err:
-	mutex_remove_waiter(lock, &waiter, task_thread_info(task));
+	mutex_remove_waiter(lock, &waiter, task);
 	spin_unlock_mutex(&lock->wait_lock, flags);
 	debug_mutex_free_waiter(&waiter);
 	mutex_release(&lock->dep_map, 1, ip);