diff --git a/include/net/dst.h b/include/net/dst.h
index 23b564d..4fedffd 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -428,20 +428,22 @@
 struct flowi;
 #ifndef CONFIG_XFRM
 static inline int xfrm_lookup(struct net *net, struct dst_entry **dst_p,
-			      struct flowi *fl, struct sock *sk, int flags)
+			      const struct flowi *fl, struct sock *sk,
+			      int flags)
 {
 	return 0;
 } 
 static inline int __xfrm_lookup(struct net *net, struct dst_entry **dst_p,
-				struct flowi *fl, struct sock *sk, int flags)
+				const struct flowi *fl, struct sock *sk,
+				int flags)
 {
 	return 0;
 }
 #else
 extern int xfrm_lookup(struct net *net, struct dst_entry **dst_p,
-		       struct flowi *fl, struct sock *sk, int flags);
+		       const struct flowi *fl, struct sock *sk, int flags);
 extern int __xfrm_lookup(struct net *net, struct dst_entry **dst_p,
-			 struct flowi *fl, struct sock *sk, int flags);
+			 const struct flowi *fl, struct sock *sk, int flags);
 #endif
 #endif