diff --git a/include/asm-x86/socket.h b/include/asm-x86/socket.h
index 99ca648..80af9c4 100644
--- a/include/asm-x86/socket.h
+++ b/include/asm-x86/socket.h
@@ -52,4 +52,6 @@
 #define SO_TIMESTAMPNS		35
 #define SCM_TIMESTAMPNS		SO_TIMESTAMPNS
 
+#define SO_MARK			36
+
 #endif /* _ASM_SOCKET_H */