2 files changed, 22 insertions, 15 deletions

diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 9e20873148c6..8de90ea31280 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -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;
 
 		/*
diff --git a/kernel/time/time.c b/kernel/time/time.c
index 58e312e7380f..704ccd9451b0 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -179,7 +179,7 @@ int do_sys_settimeofday64(const struct timespec64 *tv, const struct timezone *tz
 		return error;
 
 	if (tz) {
-		/* Verify we're witin the +-15 hrs range */
+		/* Verify we're within the +-15 hrs range */
 		if (tz->tz_minuteswest > 15*60 || tz->tz_minuteswest < -15*60)
 			return -EINVAL;
 
@@ -548,18 +548,21 @@ EXPORT_SYMBOL(set_normalized_timespec64);
  */
 struct timespec64 ns_to_timespec64(const s64 nsec)
 {
-	struct timespec64 ts;
+	struct timespec64 ts = { 0, 0 };
 	s32 rem;
 
-	if (!nsec)
-		return (struct timespec64) {0, 0};
-
-	ts.tv_sec = div_s64_rem(nsec, NSEC_PER_SEC, &rem);
-	if (unlikely(rem < 0)) {
-		ts.tv_sec--;
-		rem += NSEC_PER_SEC;
+	if (likely(nsec > 0)) {
+		ts.tv_sec = div_u64_rem(nsec, NSEC_PER_SEC, &rem);
+		ts.tv_nsec = rem;
+	} else if (nsec < 0) {
+		/*
+		 * With negative times, tv_sec points to the earlier
+		 * second, and tv_nsec counts the nanoseconds since
+		 * then, so tv_nsec is always a positive number.
+		 */
+		ts.tv_sec = -div_u64_rem(-nsec - 1, NSEC_PER_SEC, &rem) - 1;
+		ts.tv_nsec = NSEC_PER_SEC - rem - 1;
 	}
-	ts.tv_nsec = rem;
 
 	return ts;
 }
@@ -878,10 +881,11 @@ int get_timespec64(struct timespec64 *ts,
 
 	ts->tv_sec = kts.tv_sec;
 
-	/* Zero out the padding for 32 bit systems or in compat mode */
+	/* Zero out the padding in compat mode */
 	if (in_compat_syscall())
 		kts.tv_nsec &= 0xFFFFFFFFUL;
 
+	/* In 32-bit mode, this drops the padding */
 	ts->tv_nsec = kts.tv_nsec;
 
 	return 0;