diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index d890322..f9be8fb 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -644,6 +644,8 @@ static int acpi_pci_root_start(struct acpi_device *device)
 	struct acpi_pci_root *root = acpi_driver_data(device);
 	struct acpi_pci_driver *driver;
 
+	pci_bus_add_devices(root->bus);
+
 	mutex_lock(&acpi_pci_root_lock);
 	list_for_each_entry(driver, &acpi_pci_drivers, node)
 		if (driver->add)
@@ -651,8 +653,6 @@ static int acpi_pci_root_start(struct acpi_device *device)
 	acpiphp_add_bridge(root);
 	mutex_unlock(&acpi_pci_root_lock);
 
-	pci_bus_add_devices(root->bus);
-
 	return 0;
 }