SDT tables is used by the SN kernel IO "fixup" code (which is called at boot and hotplug time). On hotplugs (i.e. enable_slot()), if running with an ACPI capable prom, attempt to obtain a new ACPI SSDT table for the slot being hotplugged. If successful, add the table to the ACPI namespace (acpi_load_table()) and then walk the new devices and add them to the ACPI infrastructure (acpi_bus_add()). On hot unplugs (i.e. disable_slot()), if running with an ACPI capable prom, attempt to remove the SSDT table associated with the slot from the ACPI namespace (acpi_unload_table_id()) and infastructure (acpi_bus_trim()). From: John Keller A bug was fixed where the sgi hotplug driver was removing the slot's SSDT table from the ACPI namespace a bit too early in disable_slot(). Also, we now call acpi_bus_start() subsequent to acpi_bus_add(). Signed-off-by: Aaron Young Cc: Greg KH Cc: "Luck, Tony" Signed-off-by: Andrew Morton Signed-off-by: Len Brown ?Ò3ô–8x