Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/sc…

…m/linux/kernel/git/tip/tip

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clockevents: Set noop handler in clockevents_exchange_device()
  tick-broadcast: Stop active broadcast device when replacing it
  clocksource: Fix bug with max_deferment margin calculation
  rtc: Fix some bugs that allowed accumulating time drift in suspend/resume
  rtc: Disable the alarm in the hardware

drivers/rtc/class.c

@@ -63,7 +63,7 @@ static int rtc_suspend(struct device *dev, pm_message_t mesg)
 	 */
 	delta = timespec_sub(old_system, old_rtc);
 	delta_delta = timespec_sub(delta, old_delta);
-	if (abs(delta_delta.tv_sec)  >= 2) {
+	if (delta_delta.tv_sec < -2 || delta_delta.tv_sec >= 2) {
 		/*
 		 * if delta_delta is too large, assume time correction
 		 * has occured and set old_delta to the current delta.
@@ -97,9 +97,8 @@ static int rtc_resume(struct device *dev)
 	rtc_tm_to_time(&tm, &new_rtc.tv_sec);
 	new_rtc.tv_nsec = 0;
 
-	if (new_rtc.tv_sec <= old_rtc.tv_sec) {
-		if (new_rtc.tv_sec < old_rtc.tv_sec)
-			pr_debug("%s:  time travel!\n", dev_name(&rtc->dev));
+	if (new_rtc.tv_sec < old_rtc.tv_sec) {
+		pr_debug("%s:  time travel!\n", dev_name(&rtc->dev));
 		return 0;
 	}
 
@@ -116,7 +115,8 @@ static int rtc_resume(struct device *dev)
 	sleep_time = timespec_sub(sleep_time,
 			timespec_sub(new_system, old_system));
 
-	timekeeping_inject_sleeptime(&sleep_time);
+	if (sleep_time.tv_sec >= 0)
+		timekeeping_inject_sleeptime(&sleep_time);
 	return 0;
 }
 

drivers/rtc/interface.c

@@ -319,6 +319,20 @@ int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
 }
 EXPORT_SYMBOL_GPL(rtc_read_alarm);
 
+static int ___rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
+{
+	int err;
+
+	if (!rtc->ops)
+		err = -ENODEV;
+	else if (!rtc->ops->set_alarm)
+		err = -EINVAL;
+	else
+		err = rtc->ops->set_alarm(rtc->dev.parent, alarm);
+
+	return err;
+}
+
 static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
 {
 	struct rtc_time tm;
@@ -342,14 +356,7 @@ static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
 	 * over right here, before we set the alarm.
 	 */
 
-	if (!rtc->ops)
-		err = -ENODEV;
-	else if (!rtc->ops->set_alarm)
-		err = -EINVAL;
-	else
-		err = rtc->ops->set_alarm(rtc->dev.parent, alarm);
-
-	return err;
+	return ___rtc_set_alarm(rtc, alarm);
 }
 
 int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
@@ -763,6 +770,20 @@ static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer)
 	return 0;
 }
 
+static void rtc_alarm_disable(struct rtc_device *rtc)
+{
+	struct rtc_wkalrm alarm;
+	struct rtc_time tm;
+
+	__rtc_read_time(rtc, &tm);
+
+	alarm.time = rtc_ktime_to_tm(ktime_add(rtc_tm_to_ktime(tm),
+				     ktime_set(300, 0)));
+	alarm.enabled = 0;
+
+	___rtc_set_alarm(rtc, &alarm);
+}
+
 /**
  * rtc_timer_remove - Removes a rtc_timer from the rtc_device timerqueue
  * @rtc rtc device
@@ -784,8 +805,10 @@ static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer)
 		struct rtc_wkalrm alarm;
 		int err;
 		next = timerqueue_getnext(&rtc->timerqueue);
-		if (!next)
+		if (!next) {
+			rtc_alarm_disable(rtc);
 			return;
+		}
 		alarm.time = rtc_ktime_to_tm(next->expires);
 		alarm.enabled = 1;
 		err = __rtc_set_alarm(rtc, &alarm);
@@ -847,7 +870,8 @@ void rtc_timer_do_work(struct work_struct *work)
 		err = __rtc_set_alarm(rtc, &alarm);
 		if (err == -ETIME)
 			goto again;
-	}
+	} else
+		rtc_alarm_disable(rtc);
 
 	mutex_unlock(&rtc->ops_lock);
 }

kernel/time/clockevents.c

@@ -387,6 +387,7 @@ void clockevents_exchange_device(struct clock_event_device *old,
 	 * released list and do a notify add later.
 	 */
 	if (old) {
+		old->event_handler = clockevents_handle_noop;
 		clockevents_set_mode(old, CLOCK_EVT_MODE_UNUSED);
 		list_del(&old->list);
 		list_add(&old->list, &clockevents_released);

kernel/time/clocksource.c

@@ -548,7 +548,7 @@ static u64 clocksource_max_deferment(struct clocksource *cs)
 	 * note a margin of 12.5% is used because this can be computed with
 	 * a shift, versus say 10% which would require division.
 	 */
-	return max_nsecs - (max_nsecs >> 5);
+	return max_nsecs - (max_nsecs >> 3);
 }
 
 #ifndef CONFIG_ARCH_USES_GETTIMEOFFSET
@@ -669,7 +669,7 @@ void __clocksource_updatefreq_scale(struct clocksource *cs, u32 scale, u32 freq)
 	 * ~ 0.06ppm granularity for NTP. We apply the same 12.5%
 	 * margin as we do in clocksource_max_deferment()
 	 */
-	sec = (cs->mask - (cs->mask >> 5));
+	sec = (cs->mask - (cs->mask >> 3));
 	do_div(sec, freq);
 	do_div(sec, scale);
 	if (!sec)

kernel/time/tick-broadcast.c

@@ -71,7 +71,7 @@ int tick_check_broadcast_device(struct clock_event_device *dev)
 	     (dev->features & CLOCK_EVT_FEAT_C3STOP))
 		return 0;
 
-	clockevents_exchange_device(NULL, dev);
+	clockevents_exchange_device(tick_broadcast_device.evtdev, dev);
 	tick_broadcast_device.evtdev = dev;
 	if (!cpumask_empty(tick_get_broadcast_mask()))
 		tick_broadcast_start_periodic(dev);