diff --git a/arch/i386/kernel/io_apic.c b/arch/i386/kernel/io_apic.c
index 7554f8fd874ac2dddefaed39edb0857bf6c1b589..f2dd218d88cb64b9fe4bfa083134e7c63a9684b2 100644
--- a/arch/i386/kernel/io_apic.c
+++ b/arch/i386/kernel/io_apic.c
@@ -1649,7 +1649,7 @@ static void __init enable_IO_APIC(void)
 	for(apic = 0; apic < nr_ioapics; apic++) {
 		int pin;
 		/* See if any of the pins is in ExtINT mode */
-		for(pin = 0; pin < nr_ioapic_registers[i]; pin++) {
+		for (pin = 0; pin < nr_ioapic_registers[apic]; pin++) {
 			struct IO_APIC_route_entry entry;
 			spin_lock_irqsave(&ioapic_lock, flags);
 			*(((int *)&entry) + 0) = io_apic_read(apic, 0x10 + 2 * pin);
diff --git a/arch/x86_64/kernel/io_apic.c b/arch/x86_64/kernel/io_apic.c
index 83ea86e0633a975d3033041785a598064932d4fd..6c938c60fa3b25acaf46616f2e153543fc402954 100644
--- a/arch/x86_64/kernel/io_apic.c
+++ b/arch/x86_64/kernel/io_apic.c
@@ -47,6 +47,9 @@ static int no_timer_check;
 
 int disable_timer_pin_1 __initdata;
 
+/* Where if anywhere is the i8259 connect in external int mode */
+static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
+
 static DEFINE_SPINLOCK(ioapic_lock);
 
 /*
@@ -361,7 +364,7 @@ static int find_irq_entry(int apic, int pin, int type)
 /*
  * Find the pin to which IRQ[irq] (ISA) is connected
  */
-static int find_isa_irq_pin(int irq, int type)
+static int __init find_isa_irq_pin(int irq, int type)
 {
 	int i;
 
@@ -379,6 +382,31 @@ static int find_isa_irq_pin(int irq, int type)
 	return -1;
 }
 
+static int __init find_isa_irq_apic(int irq, int type)
+{
+	int i;
+
+	for (i = 0; i < mp_irq_entries; i++) {
+		int lbus = mp_irqs[i].mpc_srcbus;
+
+		if ((mp_bus_id_to_type[lbus] == MP_BUS_ISA ||
+		     mp_bus_id_to_type[lbus] == MP_BUS_EISA ||
+		     mp_bus_id_to_type[lbus] == MP_BUS_MCA) &&
+		    (mp_irqs[i].mpc_irqtype == type) &&
+		    (mp_irqs[i].mpc_srcbusirq == irq))
+			break;
+	}
+	if (i < mp_irq_entries) {
+		int apic;
+		for(apic = 0; apic < nr_ioapics; apic++) {
+			if (mp_ioapics[apic].mpc_apicid == mp_irqs[i].mpc_dstapic)
+				return apic;
+		}
+	}
+
+	return -1;
+}
+
 /*
  * Find a specific PCI IRQ entry.
  * Not an __init, possibly needed by modules
@@ -872,7 +900,7 @@ static void __init setup_IO_APIC_irqs(void)
  * Set up the 8259A-master output pin as broadcast to all
  * CPUs.
  */
-static void __init setup_ExtINT_IRQ0_pin(unsigned int pin, int vector)
+static void __init setup_ExtINT_IRQ0_pin(unsigned int apic, unsigned int pin, int vector)
 {
 	struct IO_APIC_route_entry entry;
 	unsigned long flags;
@@ -906,8 +934,8 @@ static void __init setup_ExtINT_IRQ0_pin(unsigned int pin, int vector)
 	 * Add it to the IO-APIC irq-routing table:
 	 */
 	spin_lock_irqsave(&ioapic_lock, flags);
-	io_apic_write(0, 0x11+2*pin, *(((int *)&entry)+1));
-	io_apic_write(0, 0x10+2*pin, *(((int *)&entry)+0));
+	io_apic_write(apic, 0x11+2*pin, *(((int *)&entry)+1));
+	io_apic_write(apic, 0x10+2*pin, *(((int *)&entry)+0));
 	spin_unlock_irqrestore(&ioapic_lock, flags);
 
 	enable_8259A_irq(0);
@@ -1186,7 +1214,8 @@ void __apicdebuginit print_PIC(void)
 static void __init enable_IO_APIC(void)
 {
 	union IO_APIC_reg_01 reg_01;
-	int i;
+	int i8259_apic, i8259_pin;
+	int i, apic;
 	unsigned long flags;
 
 	for (i = 0; i < PIN_MAP_SIZE; i++) {
@@ -1200,11 +1229,48 @@ static void __init enable_IO_APIC(void)
 	/*
 	 * The number of IO-APIC IRQ registers (== #pins):
 	 */
-	for (i = 0; i < nr_ioapics; i++) {
+	for (apic = 0; apic < nr_ioapics; apic++) {
 		spin_lock_irqsave(&ioapic_lock, flags);
-		reg_01.raw = io_apic_read(i, 1);
+		reg_01.raw = io_apic_read(apic, 1);
 		spin_unlock_irqrestore(&ioapic_lock, flags);
-		nr_ioapic_registers[i] = reg_01.bits.entries+1;
+		nr_ioapic_registers[apic] = reg_01.bits.entries+1;
+	}
+	for(apic = 0; apic < nr_ioapics; apic++) {
+		int pin;
+		/* See if any of the pins is in ExtINT mode */
+		for (pin = 0; pin < nr_ioapic_registers[apic]; pin++) {
+			struct IO_APIC_route_entry entry;
+			spin_lock_irqsave(&ioapic_lock, flags);
+			*(((int *)&entry) + 0) = io_apic_read(apic, 0x10 + 2 * pin);
+			*(((int *)&entry) + 1) = io_apic_read(apic, 0x11 + 2 * pin);
+			spin_unlock_irqrestore(&ioapic_lock, flags);
+
+
+			/* If the interrupt line is enabled and in ExtInt mode
+			 * I have found the pin where the i8259 is connected.
+			 */
+			if ((entry.mask == 0) && (entry.delivery_mode == dest_ExtINT)) {
+				ioapic_i8259.apic = apic;
+				ioapic_i8259.pin  = pin;
+				goto found_i8259;
+			}
+		}
+	}
+ found_i8259:
+	/* Look to see what if the MP table has reported the ExtINT */
+	i8259_pin  = find_isa_irq_pin(0, mp_ExtINT);
+	i8259_apic = find_isa_irq_apic(0, mp_ExtINT);
+	/* Trust the MP table if nothing is setup in the hardware */
+	if ((ioapic_i8259.pin == -1) && (i8259_pin >= 0)) {
+		printk(KERN_WARNING "ExtINT not setup in hardware but reported by MP table\n");
+		ioapic_i8259.pin  = i8259_pin;
+		ioapic_i8259.apic = i8259_apic;
+	}
+	/* Complain if the MP table and the hardware disagree */
+	if (((ioapic_i8259.apic != i8259_apic) || (ioapic_i8259.pin != i8259_pin)) &&
+		(i8259_pin >= 0) && (ioapic_i8259.pin >= 0))
+	{
+		printk(KERN_WARNING "ExtINT in hardware and MP table differ\n");
 	}
 
 	/*
@@ -1218,7 +1284,6 @@ static void __init enable_IO_APIC(void)
  */
 void disable_IO_APIC(void)
 {
-	int pin;
 	/*
 	 * Clear the IO-APIC before rebooting:
 	 */
@@ -1229,8 +1294,7 @@ void disable_IO_APIC(void)
 	 * Put that IOAPIC in virtual wire mode
 	 * so legacy interrupts can be delivered.
 	 */
-	pin = find_isa_irq_pin(0, mp_ExtINT);
-	if (pin != -1) {
+	if (ioapic_i8259.pin != -1) {
 		struct IO_APIC_route_entry entry;
 		unsigned long flags;
 
@@ -1241,21 +1305,22 @@ void disable_IO_APIC(void)
 		entry.polarity        = 0; /* High */
 		entry.delivery_status = 0;
 		entry.dest_mode       = 0; /* Physical */
-		entry.delivery_mode   = 7; /* ExtInt */
+		entry.delivery_mode   = dest_ExtINT; /* ExtInt */
 		entry.vector          = 0;
 		entry.dest.physical.physical_dest = 0;
 
-
 		/*
 		 * Add it to the IO-APIC irq-routing table:
 		 */
 		spin_lock_irqsave(&ioapic_lock, flags);
-		io_apic_write(0, 0x11+2*pin, *(((int *)&entry)+1));
-		io_apic_write(0, 0x10+2*pin, *(((int *)&entry)+0));
+		io_apic_write(ioapic_i8259.apic, 0x11+2*ioapic_i8259.pin,
+			*(((int *)&entry)+1));
+		io_apic_write(ioapic_i8259.apic, 0x10+2*ioapic_i8259.pin,
+			*(((int *)&entry)+0));
 		spin_unlock_irqrestore(&ioapic_lock, flags);
 	}
 
-	disconnect_bsp_APIC(pin != -1);
+	disconnect_bsp_APIC(ioapic_i8259.pin != -1);
 }
 
 /*
@@ -1624,20 +1689,21 @@ static void setup_nmi (void)
  */
 static inline void unlock_ExtINT_logic(void)
 {
-	int pin, i;
+	int apic, pin, i;
 	struct IO_APIC_route_entry entry0, entry1;
 	unsigned char save_control, save_freq_select;
 	unsigned long flags;
 
-	pin = find_isa_irq_pin(8, mp_INT);
+	pin  = find_isa_irq_pin(8, mp_INT);
+	apic = find_isa_irq_apic(8, mp_INT);
 	if (pin == -1)
 		return;
 
 	spin_lock_irqsave(&ioapic_lock, flags);
-	*(((int *)&entry0) + 1) = io_apic_read(0, 0x11 + 2 * pin);
-	*(((int *)&entry0) + 0) = io_apic_read(0, 0x10 + 2 * pin);
+	*(((int *)&entry0) + 1) = io_apic_read(apic, 0x11 + 2 * pin);
+	*(((int *)&entry0) + 0) = io_apic_read(apic, 0x10 + 2 * pin);
 	spin_unlock_irqrestore(&ioapic_lock, flags);
-	clear_IO_APIC_pin(0, pin);
+	clear_IO_APIC_pin(apic, pin);
 
 	memset(&entry1, 0, sizeof(entry1));
 
@@ -1650,8 +1716,8 @@ static inline void unlock_ExtINT_logic(void)
 	entry1.vector = 0;
 
 	spin_lock_irqsave(&ioapic_lock, flags);
-	io_apic_write(0, 0x11 + 2 * pin, *(((int *)&entry1) + 1));
-	io_apic_write(0, 0x10 + 2 * pin, *(((int *)&entry1) + 0));
+	io_apic_write(apic, 0x11 + 2 * pin, *(((int *)&entry1) + 1));
+	io_apic_write(apic, 0x10 + 2 * pin, *(((int *)&entry1) + 0));
 	spin_unlock_irqrestore(&ioapic_lock, flags);
 
 	save_control = CMOS_READ(RTC_CONTROL);
@@ -1669,11 +1735,11 @@ static inline void unlock_ExtINT_logic(void)
 
 	CMOS_WRITE(save_control, RTC_CONTROL);
 	CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
-	clear_IO_APIC_pin(0, pin);
+	clear_IO_APIC_pin(apic, pin);
 
 	spin_lock_irqsave(&ioapic_lock, flags);
-	io_apic_write(0, 0x11 + 2 * pin, *(((int *)&entry0) + 1));
-	io_apic_write(0, 0x10 + 2 * pin, *(((int *)&entry0) + 0));
+	io_apic_write(apic, 0x11 + 2 * pin, *(((int *)&entry0) + 1));
+	io_apic_write(apic, 0x10 + 2 * pin, *(((int *)&entry0) + 0));
 	spin_unlock_irqrestore(&ioapic_lock, flags);
 }
 
@@ -1685,7 +1751,7 @@ static inline void unlock_ExtINT_logic(void)
  */
 static inline void check_timer(void)
 {
-	int pin1, pin2;
+	int apic1, pin1, apic2, pin2;
 	int vector;
 
 	/*
@@ -1706,10 +1772,13 @@ static inline void check_timer(void)
 	init_8259A(1);
 	enable_8259A_irq(0);
 
-	pin1 = find_isa_irq_pin(0, mp_INT);
-	pin2 = find_isa_irq_pin(0, mp_ExtINT);
+	pin1  = find_isa_irq_pin(0, mp_INT);
+	apic1 = find_isa_irq_apic(0, mp_INT);
+	pin2  = ioapic_i8259.pin;
+	apic2 = ioapic_i8259.apic;
 
-	apic_printk(APIC_VERBOSE,KERN_INFO "..TIMER: vector=0x%02X pin1=%d pin2=%d\n", vector, pin1, pin2);
+	apic_printk(APIC_VERBOSE,KERN_INFO "..TIMER: vector=0x%02X apic1=%d pin1=%d apic2=%d pin2=%d\n",
+		vector, apic1, pin1, apic2, pin2);
 
 	if (pin1 != -1) {
 		/*
@@ -1727,17 +1796,20 @@ static inline void check_timer(void)
 				clear_IO_APIC_pin(0, pin1);
 			return;
 		}
-		clear_IO_APIC_pin(0, pin1);
-		apic_printk(APIC_QUIET,KERN_ERR "..MP-BIOS bug: 8254 timer not connected to IO-APIC\n");
+		clear_IO_APIC_pin(apic1, pin1);
+		apic_printk(APIC_QUIET,KERN_ERR "..MP-BIOS bug: 8254 timer not "
+				"connected to IO-APIC\n");
 	}
 
-	apic_printk(APIC_VERBOSE,KERN_INFO "...trying to set up timer (IRQ0) through the 8259A ... ");
+	apic_printk(APIC_VERBOSE,KERN_INFO "...trying to set up timer (IRQ0) "
+				"through the 8259A ... ");
 	if (pin2 != -1) {
-		apic_printk(APIC_VERBOSE,"\n..... (found pin %d) ...", pin2);
+		apic_printk(APIC_VERBOSE,"\n..... (found apic %d pin %d) ...",
+			apic2, pin2);
 		/*
 		 * legacy devices should be connected to IO APIC #0
 		 */
-		setup_ExtINT_IRQ0_pin(pin2, vector);
+		setup_ExtINT_IRQ0_pin(apic2, pin2, vector);
 		if (timer_irq_works()) {
 			printk("works.\n");
 			nmi_watchdog_default();
@@ -1749,7 +1821,7 @@ static inline void check_timer(void)
 		/*
 		 * Cleanup, just in case ...
 		 */
-		clear_IO_APIC_pin(0, pin2);
+		clear_IO_APIC_pin(apic2, pin2);
 	}
 	printk(" failed.\n");