diff --git a/arch/x86/pci/pci.h b/arch/x86/pci/pci.h
index 15b9cf6b..1959018 100644
--- a/arch/x86/pci/pci.h
+++ b/arch/x86/pci/pci.h
@@ -96,6 +96,7 @@
 extern struct pci_raw_ops *raw_pci_ext_ops;
 
 extern struct pci_raw_ops pci_direct_conf1;
+extern bool port_cf9_safe;
 
 /* arch_initcall level */
 extern int pci_direct_probe(void);