ACPI: Properly handle an ISO reassigning the ACPI interrupt. Big thanks to

John Stultz.

arch/i386/kernel/mpparse.c

@@ -1026,8 +1026,14 @@ void __init mp_config_ioapic_for_sci(int irq)
 
 		while ((void *) entry < madt_end) {
                 	if (entry->header.type == ACPI_MADT_INT_SRC_OVR &&
-			    acpi_fadt.sci_int == entry->global_irq)
+			    acpi_fadt.sci_int == entry->bus_irq) {
+				/*
+				 * ACPI should use the settings in the
+				 * ISO for its SCI. Do not continue.
+				 */
+				acpi_fadt.sci_int = entry->global_irq;
                 		return;
+			}
 
                 	entry = (struct acpi_table_int_src_ovr *)
                 	        ((unsigned long) entry + entry->header.length);

drivers/acpi/osl.c

@@ -223,6 +223,13 @@ acpi_irq(int irq, void *dev_id, struct pt_regs *regs)
 acpi_status
 acpi_os_install_interrupt_handler(u32 irq, OSD_HANDLER handler, void *context)
 {
+	/*
+	 * Ignore the irq from the core, and use the value in our copy of the
+	 * FADT. It may not be the same if an interrupt source override exists
+	 * for the SCI.
+	 */
+	irq = acpi_fadt.sci_int;
+
 #ifdef CONFIG_IA64
 	irq = gsi_to_vector(irq);
 #endif