Index: sys/x86/x86/intr_machdep.c
===================================================================
--- sys/x86/x86/intr_machdep.c
+++ sys/x86/x86/intr_machdep.c
@@ -604,6 +604,25 @@
 			}
 		}
 	}
+
+	/*
+	 * Make a second pass to round-robin disabled sources, in case they are
+	 * enabled later.
+	 */
+	for (i = 0; i < NUM_IO_INTS; i++) {
+		isrc = interrupt_sources[i];
+		if (isrc != NULL && isrc->is_handlers == 0) {
+			cpu = isrc->is_event->ie_cpu;
+			if (cpu == NOCPU)
+				cpu = current_cpu;
+			if (isrc->is_pic->pic_assign_cpu(isrc,
+			    cpu_apic_ids[cpu]) == 0) {
+				isrc->is_cpu = cpu;
+				if (isrc->is_event->ie_cpu == NOCPU)
+					intr_next_cpu();
+			}
+		}
+	}
 	sx_xunlock(&intrsrc_lock);
 }
 SYSINIT(intr_shuffle_irqs, SI_SUB_SMP, SI_ORDER_SECOND, intr_shuffle_irqs,