diff --git a/sys/ia64/ia64/mp_machdep.c b/sys/ia64/ia64/mp_machdep.c
index 8e71b35e00aa..a29b3995d510 100644
--- a/sys/ia64/ia64/mp_machdep.c
+++ b/sys/ia64/ia64/mp_machdep.c
@@ -65,6 +65,8 @@ __FBSDID("$FreeBSD$");
 
 extern uint64_t bdata[];
 
+extern int smp_disabled;
+
 MALLOC_DEFINE(M_SMP, "SMP", "SMP related allocations");
 
 void ia64_ap_startup(void);
@@ -294,6 +296,9 @@ cpu_mp_add(u_int acpi_id, u_int id, u_int eid)
 	void *dpcpu;
 	u_int cpuid, sapic_id;
 
+	if (smp_disabled)
+		return;
+
 	sapic_id = SAPIC_ID_SET(id, eid);
 	cpuid = (IA64_LID_GET_SAPIC_ID(ia64_get_lid()) == sapic_id)
 	    ? 0 : smp_cpus++;