--- y/kernel/time/hrtimer.c
+++ h/kernel/time/hrtimer.c
@@ -1647,6 +1647,7 @@ static void __run_hrtimer(struct hrtimer
 	enum hrtimer_restart (*fn)(struct hrtimer *);
 	bool expires_in_hardirq;
 	int restart;
+	unsigned long ts;
 
 	lockdep_assert_held(&cpu_base->lock);
 
@@ -1682,8 +1683,12 @@ static void __run_hrtimer(struct hrtimer
 	trace_hrtimer_expire_entry(timer, now);
 	expires_in_hardirq = lockdep_hrtimer_enter(timer);
 
+	ts = jiffies + 4;
+
 	restart = fn(timer);
 
+	WARN_ONCE(time_after(jiffies, ts), "hrtimer hog %ps ran longer than 4 ticks\n", fn);
+
 	lockdep_hrtimer_exit(expires_in_hardirq);
 	trace_hrtimer_expire_exit(timer);
 	raw_spin_lock_irq(&cpu_base->lock);