diff --git a/include/asm-x86_64/proto.h b/include/asm-x86_64/proto.h
index 977fe58e971c..8abf2a43c944 100644
--- a/include/asm-x86_64/proto.h
+++ b/include/asm-x86_64/proto.h
@@ -127,7 +127,6 @@ extern int fix_aperture;
 #define iommu_aperture 0
 #define iommu_aperture_allowed 0
 #endif
-extern int force_iommu;
 
 extern int reboot_force;
 extern int notsc_setup(char *);