diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h
index 32e130b560fa697e334bfaaecf613234acdb060f..10bbb4273f7da4db28d65e14241d23de53d7070b 100644
--- a/include/net/ip_tunnels.h
+++ b/include/net/ip_tunnels.h
@@ -73,6 +73,7 @@ struct ip_tunnel {
 #define TUNNEL_REC	__cpu_to_be16(0x20)
 #define TUNNEL_VERSION	__cpu_to_be16(0x40)
 #define TUNNEL_NO_KEY	__cpu_to_be16(0x80)
+#define TUNNEL_DONT_FRAGMENT    __cpu_to_be16(0x0100)
 
 struct tnl_ptk_info {
 	__be16 flags;