diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index c3fed31..18ff4e5 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -190,7 +190,7 @@
 	struct acpi_pci_root *root = NULL;
 	struct acpi_pci_root *tmp;
 	acpi_status status = AE_OK;
-	unsigned long value = 0;
+	unsigned long long value = 0;
 	acpi_handle handle = NULL;
 	struct acpi_device *child;