diff --git a/kernel/sched.c b/kernel/sched.c
index 1a5f73c..e46b5af 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -221,9 +221,8 @@
 
 		now = hrtimer_cb_get_time(&rt_b->rt_period_timer);
 		hrtimer_forward(&rt_b->rt_period_timer, now, rt_b->rt_period);
-		hrtimer_start(&rt_b->rt_period_timer,
-			      rt_b->rt_period_timer.expires,
-			      HRTIMER_MODE_ABS);
+		hrtimer_start_expires(&rt_b->rt_period_timer,
+				HRTIMER_MODE_ABS);
 	}
 	spin_unlock(&rt_b->rt_runtime_lock);
 }
@@ -1058,7 +1057,7 @@
 	struct hrtimer *timer = &rq->hrtick_timer;
 	ktime_t time = ktime_add_ns(timer->base->get_time(), delay);
 
-	timer->expires = time;
+	hrtimer_set_expires(timer, time);
 
 	if (rq == this_rq()) {
 		hrtimer_restart(timer);