Merge tag 'v4.14.170' into 4.14-2.3.x-imx

This is the 4.14.170 stable release

Conflicts:
	drivers/net/phy/phy_device.c
	drivers/tty/serial/imx.c
	include/linux/platform_data/dma-imx-sdma.h
	net/wireless/util.c

1 files changed, 9 insertions, 5 deletions

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index a8fa0a896b78..3c7b400512eb 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -60,8 +60,9 @@ static void tick_do_update_jiffies64(ktime_t now)
 
 	/*
 	 * Do a quick check without holding jiffies_lock:
+	 * The READ_ONCE() pairs with two updates done later in this function.
 	 */
-	delta = ktime_sub(now, last_jiffies_update);
+	delta = ktime_sub(now, READ_ONCE(last_jiffies_update));
 	if (delta < tick_period)
 		return;
 
@@ -72,8 +73,9 @@ static void tick_do_update_jiffies64(ktime_t now)
 	if (delta >= tick_period) {
 
 		delta = ktime_sub(delta, tick_period);
-		last_jiffies_update = ktime_add(last_jiffies_update,
-						tick_period);
+		/* Pairs with the lockless read in this function. */
+		WRITE_ONCE(last_jiffies_update,
+			   ktime_add(last_jiffies_update, tick_period));
 
 		/* Slow path for long timeouts */
 		if (unlikely(delta >= tick_period)) {
@@ -81,8 +83,10 @@ static void tick_do_update_jiffies64(ktime_t now)
 
 			ticks = ktime_divns(delta, incr);
 
-			last_jiffies_update = ktime_add_ns(last_jiffies_update,
-							   incr * ticks);
+			/* Pairs with the lockless read in this function. */
+			WRITE_ONCE(last_jiffies_update,
+				   ktime_add_ns(last_jiffies_update,
+						incr * ticks));
 		}
 		do_timer(++ticks);