diff --git a/arch/x86_64/acpi/smp.cpp b/arch/x86_64/acpi/smp.cpp
index ac8bde9..bf96901 100644
--- a/arch/x86_64/acpi/smp.cpp
+++ b/arch/x86_64/acpi/smp.cpp
@@ -38,6 +38,7 @@ extern "C" void ap_trampoline_exit(void)
 
 	ap_apic_init();
 
+	cpu_set_online(cpu_id);
 	__this_ap_ok = 1;
 	irq_enable();