--- x/kernel/sched/deadline.c
+++ y/kernel/sched/deadline.c
@@ -1498,6 +1498,9 @@ static void update_curr_dl_se(struct rq
 	 * starting a new period, pushing the activation.
 	 */
 	if (dl_se->dl_defer && dl_se->dl_throttled && dl_runtime_exceeded(dl_se)) {
+		bool lock = rq != dl_se->rq;
+		struct rq_flags rf;
+		struct rq *__rq = dl_se->rq;
 		/*
 		 * If the server was previously activated - the starving condition
 		 * took place, it this point it went away because the fair scheduler
@@ -1508,7 +1511,11 @@ static void update_curr_dl_se(struct rq
 
 		hrtimer_try_to_cancel(&dl_se->dl_timer);
 
+		if (lock)
+			rq_lock(__rq, &rf);
 		replenish_dl_new_period(dl_se, dl_se->rq);
+		if (lock)
+			rq_unlock(__rq, &rf);
 
 		/*
 		 * Not being able to start the timer seems problematic. If it could not