git » linux-kernel » commit 49d670f

clockevents: prevent stale tick_next_period for onlining CPUs

clockevents: prevent stale tick_next_period for onlining CPUs

Impact: possible hang on CPU onlining in timer one shot mode.

The tick_next_period variable is only used during boot on nohz/highres
enabled systems, but for CPU onlining it needs to be maintained when
the per cpu clock events device operates in one shot mode.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 31a14e8caac..39019b3f762 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -75,6 +75,9 @@ static void tick_do_update_jiffies64(ktime_t now)
 							   incr * ticks);
 		}
 		do_timer(++ticks);
+
+		/* Keep the tick_next_period variable up to date */
+		tick_next_period = ktime_add(last_jiffies_update, tick_period);
 	}
 	write_sequnlock(&xtime_lock);
 }