Index: sys/arm64/arm64/mp_machdep.c
===================================================================
--- sys/arm64/arm64/mp_machdep.c
+++ sys/arm64/arm64/mp_machdep.c
@@ -266,9 +266,6 @@
 
 	intr_pic_init_secondary();
 
-	/* Start per-CPU event timers. */
-	cpu_initclocks_ap();
-
 #ifdef VFP
 	vfp_init();
 #endif
@@ -301,9 +298,11 @@
 static void
 smp_after_idle_runnable(void *arg __unused)
 {
+	struct thread *td;
 	struct pcpu *pc;
 	int cpu;
 
+	td = curthread;
 	for (cpu = 1; cpu < mp_ncpus; cpu++) {
 		if (bootstacks[cpu] != NULL) {
 			pc = pcpu_find(cpu);
@@ -311,7 +310,22 @@
 				cpu_spinwait();
 			kmem_free((vm_offset_t)bootstacks[cpu], PAGE_SIZE);
 		}
+
+		/*
+		 * Start any CPU-specific event timers.  This is done relatively
+		 * late to avoid processing callouts before the transition to
+		 * idlethread has put us in the proper scheduler state.
+		 */
+		thread_lock(td);
+		sched_bind(td, cpu);
+		thread_unlock(td);
+		cpu_initclocks_ap();
 	}
+
+	thread_lock(td);
+	if (sched_is_bound(td))
+		sched_unbind(td);
+	thread_unlock(td);
 }
 SYSINIT(smp_after_idle_runnable, SI_SUB_SMP, SI_ORDER_ANY,
     smp_after_idle_runnable, NULL);