Merge tag 'v5.14-rc6' into locking/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

8 files changed, 48 insertions, 36 deletions

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 095c87f97a31..bf1c00c881e4 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -760,7 +760,7 @@ static void lockdep_print_held_locks(struct task_struct *p)
 	 * It's not reliable to print a task's held locks if it's not sleeping
 	 * and it's not the current task.
 	 */
-	if (p->state == TASK_RUNNING && p != current)
+	if (p != current && task_is_running(p))
 		return;
 	for (i = 0; i < depth; i++) {
 		printk(" #%d: ", i);
@@ -843,7 +843,7 @@ static int count_matching_names(struct lock_class *new_class)
 }
 
 /* used from NMI context -- must be lockless */
-static __always_inline struct lock_class *
+static noinstr struct lock_class *
 look_up_lock_class(const struct lockdep_map *lock, unsigned int subclass)
 {
 	struct lockdep_subclass_key *key;
@@ -851,12 +851,14 @@ look_up_lock_class(const struct lockdep_map *lock, unsigned int subclass)
 	struct lock_class *class;
 
 	if (unlikely(subclass >= MAX_LOCKDEP_SUBCLASSES)) {
+		instrumentation_begin();
 		debug_locks_off();
 		printk(KERN_ERR
 			"BUG: looking up invalid subclass: %u\n", subclass);
 		printk(KERN_ERR
 			"turning off the locking correctness validator.\n");
 		dump_stack();
+		instrumentation_end();
 		return NULL;
 	}
 
@@ -5847,7 +5849,7 @@ void lock_contended(struct lockdep_map *lock, unsigned long ip)
 {
 	unsigned long flags;
 
-	trace_lock_acquired(lock, ip);
+	trace_lock_contended(lock, ip);
 
 	if (unlikely(!lock_stat || !lockdep_enabled()))
 		return;
@@ -5865,7 +5867,7 @@ void lock_acquired(struct lockdep_map *lock, unsigned long ip)
 {
 	unsigned long flags;
 
-	trace_lock_contended(lock, ip);
+	trace_lock_acquired(lock, ip);
 
 	if (unlikely(!lock_stat || !lockdep_enabled()))
 		return;
@@ -6504,6 +6506,7 @@ asmlinkage __visible void lockdep_sys_exit(void)
 void lockdep_rcu_suspicious(const char *file, const int line, const char *s)
 {
 	struct task_struct *curr = current;
+	int dl = READ_ONCE(debug_locks);
 
 	/* Note: the following can be executed concurrently, so be careful. */
 	pr_warn("\n");
@@ -6513,11 +6516,12 @@ void lockdep_rcu_suspicious(const char *file, const int line, const char *s)
 	pr_warn("-----------------------------\n");
 	pr_warn("%s:%d %s!\n", file, line, s);
 	pr_warn("\nother info that might help us debug this:\n\n");
-	pr_warn("\n%srcu_scheduler_active = %d, debug_locks = %d\n",
+	pr_warn("\n%srcu_scheduler_active = %d, debug_locks = %d\n%s",
 	       !rcu_lockdep_current_cpu_online()
 			? "RCU used illegally from offline CPU!\n"
 			: "",
-	       rcu_scheduler_active, debug_locks);
+	       rcu_scheduler_active, dl,
+	       dl ? "" : "Possible false positive due to lockdep disabling via debug_locks = 0\n");
 
 	/*
 	 * If a CPU is in the RCU-free window in idle (ie: in the section
diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c
index 806978314496..b8d9a050c337 100644
--- a/kernel/locking/lockdep_proc.c
+++ b/kernel/locking/lockdep_proc.c
@@ -70,26 +70,28 @@ static int l_show(struct seq_file *m, void *v)
 #ifdef CONFIG_DEBUG_LOCKDEP
 	seq_printf(m, " OPS:%8ld", debug_class_ops_read(class));
 #endif
-#ifdef CONFIG_PROVE_LOCKING
-	seq_printf(m, " FD:%5ld", lockdep_count_forward_deps(class));
-	seq_printf(m, " BD:%5ld", lockdep_count_backward_deps(class));
-#endif
+	if (IS_ENABLED(CONFIG_PROVE_LOCKING)) {
+		seq_printf(m, " FD:%5ld", lockdep_count_forward_deps(class));
+		seq_printf(m, " BD:%5ld", lockdep_count_backward_deps(class));
 
-	get_usage_chars(class, usage);
-	seq_printf(m, " %s", usage);
+		get_usage_chars(class, usage);
+		seq_printf(m, " %s", usage);
+	}
 
 	seq_printf(m, ": ");
 	print_name(m, class);
 	seq_puts(m, "\n");
 
-	list_for_each_entry(entry, &class->locks_after, entry) {
-		if (entry->distance == 1) {
-			seq_printf(m, " -> [%p] ", entry->class->key);
-			print_name(m, entry->class);
-			seq_puts(m, "\n");
+	if (IS_ENABLED(CONFIG_PROVE_LOCKING)) {
+		list_for_each_entry(entry, &class->locks_after, entry) {
+			if (entry->distance == 1) {
+				seq_printf(m, " -> [%p] ", entry->class->key);
+				print_name(m, entry->class);
+				seq_puts(m, "\n");
+			}
 		}
+		seq_puts(m, "\n");
 	}
-	seq_puts(m, "\n");
 
 	return 0;
 }
diff --git a/kernel/locking/mutex-debug.c b/kernel/locking/mutex-debug.c
index a7276aaf2abc..db9301591e3f 100644
--- a/kernel/locking/mutex-debug.c
+++ b/kernel/locking/mutex-debug.c
@@ -57,7 +57,7 @@ void debug_mutex_add_waiter(struct mutex *lock, struct mutex_waiter *waiter,
 	task->blocked_on = waiter;
 }
 
-void mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter,
+void debug_mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter,
 			 struct task_struct *task)
 {
 	DEBUG_LOCKS_WARN_ON(list_empty(&waiter->list));
@@ -65,7 +65,7 @@ void mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter,
 	DEBUG_LOCKS_WARN_ON(task->blocked_on != waiter);
 	task->blocked_on = NULL;
 
-	list_del_init(&waiter->list);
+	INIT_LIST_HEAD(&waiter->list);
 	waiter->task = NULL;
 }
 
diff --git a/kernel/locking/mutex-debug.h b/kernel/locking/mutex-debug.h
index 1edd3f45a4ec..53e631e1d76d 100644
--- a/kernel/locking/mutex-debug.h
+++ b/kernel/locking/mutex-debug.h
@@ -22,7 +22,7 @@ extern void debug_mutex_free_waiter(struct mutex_waiter *waiter);
 extern void debug_mutex_add_waiter(struct mutex *lock,
 				   struct mutex_waiter *waiter,
 				   struct task_struct *task);
-extern void mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter,
+extern void debug_mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter,
 				struct task_struct *task);
 extern void debug_mutex_unlock(struct mutex *lock);
 extern void debug_mutex_init(struct mutex *lock, const char *name,
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 633bf0dce3f8..21c9e5da1858 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -194,7 +194,7 @@ static inline bool __mutex_waiter_is_first(struct mutex *lock, struct mutex_wait
  * Add @waiter to a given location in the lock wait_list and set the
  * FLAG_WAITERS flag if it's the first waiter.
  */
-static void __sched
+static void
 __mutex_add_waiter(struct mutex *lock, struct mutex_waiter *waiter,
 		   struct list_head *list)
 {
@@ -205,6 +205,16 @@ __mutex_add_waiter(struct mutex *lock, struct mutex_waiter *waiter,
 		__mutex_set_flag(lock, MUTEX_FLAG_WAITERS);
 }
 
+static void
+__mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter)
+{
+	list_del(&waiter->list);
+	if (likely(list_empty(&lock->wait_list)))
+		__mutex_clear_flag(lock, MUTEX_FLAGS);
+
+	debug_mutex_remove_waiter(lock, waiter, current);
+}
+
 /*
  * Give up ownership to a specific task, when @task = NULL, this is equivalent
  * to a regular unlock. Sets PICKUP on a handoff, clears HANDOFF, preserves
@@ -914,7 +924,7 @@ __ww_mutex_add_waiter(struct mutex_waiter *waiter,
  * Lock a mutex (possibly interruptible), slowpath:
  */
 static __always_inline int __sched
-__mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
+__mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclass,
 		    struct lockdep_map *nest_lock, unsigned long ip,
 		    struct ww_acquire_ctx *ww_ctx, const bool use_ww_ctx)
 {
@@ -1053,9 +1063,7 @@ acquired:
 			__ww_mutex_check_waiters(lock, ww_ctx);
 	}
 
-	mutex_remove_waiter(lock, &waiter, current);
-	if (likely(list_empty(&lock->wait_list)))
-		__mutex_clear_flag(lock, MUTEX_FLAGS);
+	__mutex_remove_waiter(lock, &waiter);
 
 	debug_mutex_free_waiter(&waiter);
 
@@ -1072,7 +1080,7 @@ skip_wait:
 
 err:
 	__set_current_state(TASK_RUNNING);
-	mutex_remove_waiter(lock, &waiter, current);
+	__mutex_remove_waiter(lock, &waiter);
 err_early_kill:
 	spin_unlock(&lock->wait_lock);
 	debug_mutex_free_waiter(&waiter);
@@ -1082,14 +1090,14 @@ err_early_kill:
 }
 
 static int __sched
-__mutex_lock(struct mutex *lock, long state, unsigned int subclass,
+__mutex_lock(struct mutex *lock, unsigned int state, unsigned int subclass,
 	     struct lockdep_map *nest_lock, unsigned long ip)
 {
 	return __mutex_lock_common(lock, state, subclass, nest_lock, ip, NULL, false);
 }
 
 static int __sched
-__ww_mutex_lock(struct mutex *lock, long state, unsigned int subclass,
+__ww_mutex_lock(struct mutex *lock, unsigned int state, unsigned int subclass,
 		struct lockdep_map *nest_lock, unsigned long ip,
 		struct ww_acquire_ctx *ww_ctx)
 {
diff --git a/kernel/locking/mutex.h b/kernel/locking/mutex.h
index 1c2287d3fa71..f0c710b1d192 100644
--- a/kernel/locking/mutex.h
+++ b/kernel/locking/mutex.h
@@ -10,12 +10,10 @@
  * !CONFIG_DEBUG_MUTEXES case. Most of them are NOPs:
  */
 
-#define mutex_remove_waiter(lock, waiter, task) \
-		__list_del((waiter)->list.prev, (waiter)->list.next)
-
 #define debug_mutex_wake_waiter(lock, waiter)		do { } while (0)
 #define debug_mutex_free_waiter(waiter)			do { } while (0)
 #define debug_mutex_add_waiter(lock, waiter, ti)	do { } while (0)
+#define debug_mutex_remove_waiter(lock, waiter, ti)     do { } while (0)
 #define debug_mutex_unlock(lock)			do { } while (0)
 #define debug_mutex_init(lock, name, key)		do { } while (0)
 
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 406818196a9f..ad0db322ed3b 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -343,7 +343,7 @@ static __always_inline bool
 rt_mutex_cond_detect_deadlock(struct rt_mutex_waiter *waiter,
 			      enum rtmutex_chainwalk chwalk)
 {
-	if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEX))
+	if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES))
 		return waiter != NULL;
 	return chwalk == RT_MUTEX_FULL_CHAINWALK;
 }
@@ -1135,7 +1135,7 @@ void __sched rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
  *
  * Must be called with lock->wait_lock held and interrupts disabled
  */
-static int __sched __rt_mutex_slowlock(struct rt_mutex *lock, int state,
+static int __sched __rt_mutex_slowlock(struct rt_mutex *lock, unsigned int state,
 				       struct hrtimer_sleeper *timeout,
 				       struct rt_mutex_waiter *waiter)
 {
@@ -1190,7 +1190,7 @@ static void __sched rt_mutex_handle_deadlock(int res, int detect_deadlock,
 /*
  * Slow path lock function:
  */
-static int __sched rt_mutex_slowlock(struct rt_mutex *lock, int state,
+static int __sched rt_mutex_slowlock(struct rt_mutex *lock, unsigned int state,
 				     struct hrtimer_sleeper *timeout,
 				     enum rtmutex_chainwalk chwalk)
 {
diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c
index 2cad15df296f..8a595b60ca9b 100644
--- a/kernel/locking/rwsem.c
+++ b/kernel/locking/rwsem.c
@@ -889,7 +889,7 @@ rwsem_spin_on_owner(struct rw_semaphore *sem)
  * Wait for the read lock to be granted
  */
 static struct rw_semaphore __sched *
-rwsem_down_read_slowpath(struct rw_semaphore *sem, long count, int state)
+rwsem_down_read_slowpath(struct rw_semaphore *sem, long count, unsigned int state)
 {
 	long adjustment = -RWSEM_READER_BIAS;
 	long rcnt = (count >> RWSEM_READER_SHIFT);