diff --git a/arch/x86_64/acpi/apic.cpp b/arch/x86_64/acpi/apic.cpp
index 5294350..27e3ef7 100644
--- a/arch/x86_64/acpi/apic.cpp
+++ b/arch/x86_64/acpi/apic.cpp
@@ -101,7 +101,7 @@ static struct irq_hook lapic_clock_irq_hook = {
 	lapic_clock_irq,
 };
 
-void local_apic_config_timer(void)
+void local_apic_config_timer(bool bsp)
 {
 	local_apic& lapic = local_apic::get();
 
@@ -110,9 +110,11 @@ void local_apic_config_timer(void)
 	clock_wait(10);
 	lapic.write(local_apic::LVT_TIMER, APIC_LVT_INT_MASKED);
 
-	/* mask IRQ0 to block interrupts from the PIT. */
-	io_apic *irq0_apic = get_ioapic_for_irq(0);
-	irq0_apic->mask_irq(0);
+	if (bsp) {
+		/* mask IRQ0 to block interrupts from the PIT. */
+		io_apic *irq0_apic = get_ioapic_for_irq(0);
+		irq0_apic->mask_irq(0);
+	}
 
 	uint32_t total_ticks = 0xFFFFFFFF - lapic.read(local_apic::TIMER_CURCOUNT);
 
@@ -178,7 +180,7 @@ kern_status_t ap_apic_init(void)
 	local_apic_enable(madt);
 
 	//irq_enable();
-	local_apic_config_timer();
+	local_apic_config_timer(false);
 
 	return KERN_OK;
 }
@@ -205,7 +207,7 @@ kern_status_t apic_init(void)
 
 	pit_start(HZ);
 
-	local_apic_config_timer();
+	local_apic_config_timer(true);
 	pit_stop();
 
 	hook_irq(IRQ0, &lapic_clock_irq_hook);