Index: arch/amd64/include/cpu.h
===================================================================
--- arch/amd64/include/cpu.h	(revision 73e9b49f68fcee880d656c3073aeba64b022fbfc)
+++ arch/amd64/include/cpu.h	(revision 6ecc8bce45bcc67b6373d7dbfafad230f5b1ee01)
@@ -30,4 +30,5 @@
 #define __amd64_CPU_H__
 
+#define RFLAGS_IF       (1 << 9)
 #define RFLAGS_RF       (1 << 16)