diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 87ae4e3..c9ba0da 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -322,7 +322,11 @@
 	__u8			recverr:1,
 	                        sndflow:1,
 				pmtudisc:2,
-				ipv6only:1;
+				ipv6only:1,
+				srcprefs:3;	/* 001: prefer temporary address
+						 * 010: prefer public address
+						 * 100: prefer care-of address
+						 */
 	__u8			tclass;
 
 	__u32			dst_cookie;