Index: kern_timeout.c
===================================================================
RCS file: /cvs/src/sys/kern/kern_timeout.c,v
diff -u -p -r1.101 kern_timeout.c
--- kern_timeout.c	13 Jan 2025 03:21:10 -0000	1.101
+++ kern_timeout.c	29 Apr 2025 12:27:54 -0000
@@ -55,6 +55,7 @@
  *	T	timeout_mutex
  */
 struct mutex timeout_mutex = MUTEX_INITIALIZER(IPL_HIGH);
+static unsigned int timeout_running;
 
 void *softclock_si;			/* [I] softclock() interrupt handle */
 struct timeoutstat tostat;		/* [T] statistics and totals */
@@ -465,6 +466,7 @@ timeout_del_barrier(struct timeout *to)
 void
 timeout_barrier(struct timeout *to)
 {
+	struct circq *to_list;
 	struct timeout barrier;
 	struct cond c;
 	int flags;
@@ -478,29 +480,28 @@ timeout_barrier(struct timeout *to)
 	cond_init(&c);
 
 	mtx_enter(&timeout_mutex);
-
-	barrier.to_time = ticks;
-	SET(barrier.to_flags, TIMEOUT_ONQUEUE);
 	if (ISSET(flags, TIMEOUT_PROC)) {
 #ifdef MULTIPROCESSOR
 		if (ISSET(flags, TIMEOUT_MPSAFE))
-			CIRCQ_INSERT_TAIL(&timeout_proc_mp, &barrier.to_list);
+			to_list = &timeout_proc_mp;
 		else
 #endif
-			CIRCQ_INSERT_TAIL(&timeout_proc, &barrier.to_list);
-	} else
-		CIRCQ_INSERT_TAIL(&timeout_todo, &barrier.to_list);
+			to_list = &timeout_proc;
+	} else if (timeout_running)
+		to_list = &timeout_todo;
+	else {
+		mtx_leave(&timeout_mutex);
+		return;
+	}
 
+	barrier.to_time = ticks;
+	SET(barrier.to_flags, TIMEOUT_ONQUEUE);
+	CIRCQ_INSERT_TAIL(to_list, &barrier.to_list);
 	mtx_leave(&timeout_mutex);
 
-	if (ISSET(flags, TIMEOUT_PROC)) {
-#ifdef MULTIPROCESSOR
-		if (ISSET(flags, TIMEOUT_MPSAFE))
-			wakeup_one(&timeout_proc_mp);
-		else
-#endif
-			wakeup_one(&timeout_proc);
-	} else
+	if (ISSET(flags, TIMEOUT_PROC))
+		wakeup_one(to_list);
+	else
 		softintr_schedule(softclock_si);
 
 	cond_wait(&c, "tmobar");
@@ -689,7 +690,9 @@ softclock_process_kclock_timeout(struct 
 			CIRCQ_INSERT_TAIL(&timeout_proc, &to->to_list);
 		return;
 	}
+	timeout_running = 1;
 	timeout_run(to);
+	timeout_running = 0;
 	tostat.tos_run_softclock++;
 }
 
@@ -716,7 +719,9 @@ softclock_process_tick_timeout(struct ti
 			CIRCQ_INSERT_TAIL(&timeout_proc, &to->to_list);
 		return;
 	}
+	timeout_running = 1;
 	timeout_run(to);
+	timeout_running = 0;
 	tostat.tos_run_softclock++;
 }