1 files changed, 12 insertions, 9 deletions

diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 0d4dc241c0fb..8de90ea31280 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -164,7 +164,7 @@ struct hrtimer_clock_base *lock_hrtimer_base(const struct hrtimer *timer,
 	struct hrtimer_clock_base *base;
 
 	for (;;) {
-		base = timer->base;
+		base = READ_ONCE(timer->base);
 		if (likely(base != &migration_base)) {
 			raw_spin_lock_irqsave(&base->cpu_base->lock, *flags);
 			if (likely(base == timer->base))
@@ -244,7 +244,7 @@ again:
 			return base;
 
 		/* See the comment in lock_hrtimer_base() */
-		timer->base = &migration_base;
+		WRITE_ONCE(timer->base, &migration_base);
 		raw_spin_unlock(&base->cpu_base->lock);
 		raw_spin_lock(&new_base->cpu_base->lock);
 
@@ -253,10 +253,10 @@ again:
 			raw_spin_unlock(&new_base->cpu_base->lock);
 			raw_spin_lock(&base->cpu_base->lock);
 			new_cpu_base = this_cpu_base;
-			timer->base = base;
+			WRITE_ONCE(timer->base, base);
 			goto again;
 		}
-		timer->base = new_base;
+		WRITE_ONCE(timer->base, new_base);
 	} else {
 		if (new_cpu_base != this_cpu_base &&
 		    hrtimer_check_target(timer, new_base)) {
@@ -966,7 +966,8 @@ static int enqueue_hrtimer(struct hrtimer *timer,
 
 	base->cpu_base->active_bases |= 1 << base->index;
 
-	timer->state = HRTIMER_STATE_ENQUEUED;
+	/* Pairs with the lockless read in hrtimer_is_queued() */
+	WRITE_ONCE(timer->state, HRTIMER_STATE_ENQUEUED);
 
 	return timerqueue_add(&base->active, &timer->node);
 }
@@ -988,7 +989,8 @@ static void __remove_hrtimer(struct hrtimer *timer,
 	struct hrtimer_cpu_base *cpu_base = base->cpu_base;
 	u8 state = timer->state;
 
-	timer->state = newstate;
+	/* Pairs with the lockless read in hrtimer_is_queued() */
+	WRITE_ONCE(timer->state, newstate);
 	if (!(state & HRTIMER_STATE_ENQUEUED))
 		return;
 
@@ -1013,8 +1015,9 @@ static void __remove_hrtimer(struct hrtimer *timer,
 static inline int
 remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base, bool restart)
 {
-	if (hrtimer_is_queued(timer)) {
-		u8 state = timer->state;
+	u8 state = timer->state;
+
+	if (state & HRTIMER_STATE_ENQUEUED) {
 		int reprogram;
 
 		/*
@@ -1940,7 +1943,7 @@ out:
 	return ret;
 }
 
-#if !defined(CONFIG_64BIT_TIME) || defined(CONFIG_64BIT)
+#ifdef CONFIG_64BIT
 
 SYSCALL_DEFINE2(nanosleep, struct __kernel_timespec __user *, rqtp,
 		struct __kernel_timespec __user *, rmtp)