[PATCH 4.9 095/104] rtc: set the alarm to the next expiring timer

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Alexandre Belloni <alexandre.bell...@free-electrons.com>


[ Upstream commit 74717b28cb32e1ad3c1042cafd76b264c8c0f68d ]

If there is any non expired timer in the queue, the RTC alarm is never set.
This is an issue when adding a timer that expires before the next non
expired timer.

Ensure the RTC alarm is set in that case.

Fixes: 2b2f5ff00f63 ("rtc: interface: ignore expired timers when enqueuing new 
timers")
Signed-off-by: Alexandre Belloni <alexandre.bell...@free-electrons.com>
Signed-off-by: Sasha Levin <alexander.le...@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 drivers/rtc/interface.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/rtc/interface.c
+++ b/drivers/rtc/interface.c
@@ -772,7 +772,7 @@ static int rtc_timer_enqueue(struct rtc_
        }
 
        timerqueue_add(&rtc->timerqueue, &timer->node);
-       if (!next) {
+       if (!next || ktime_before(timer->node.expires, next->expires)) {
                struct rtc_wkalrm alarm;
                int err;
                alarm.time = rtc_ktime_to_tm(timer->node.expires);