--- zzzz-none-000/linux-2.6.39.4/net/ipv6/Kconfig	2011-08-03 19:43:28.000000000 +0000
+++ puma6-atom-6490-729/linux-2.6.39.4/net/ipv6/Kconfig	2021-11-10 13:38:18.000000000 +0000
@@ -69,7 +69,7 @@
 
 config INET6_AH
 	tristate "IPv6: AH transformation"
-	select XFRM
+	select XFRM_ALGO
 	select CRYPTO
 	select CRYPTO_HMAC
 	select CRYPTO_MD5
@@ -81,7 +81,7 @@
 
 config INET6_ESP
 	tristate "IPv6: ESP transformation"
-	select XFRM
+	select XFRM_ALGO
 	select CRYPTO
 	select CRYPTO_AUTHENC
 	select CRYPTO_HMAC
@@ -201,6 +201,22 @@
 
 	  If unsure, say N.
 
+config IPV6_GRE
+	tristate "IPv6: GRE tunnel"
+	select IPV6_TUNNEL
+	---help---
+	  Tunneling means encapsulating data of one protocol type within
+	  another protocol and sending it over a channel that understands the
+	  encapsulating protocol. This particular tunneling driver implements
+	  GRE (Generic Routing Encapsulation) and at this time allows
+	  encapsulating of IPv4 or IPv6 over existing IPv6 infrastructure.
+	  This driver is useful if the other endpoint is a Cisco router: Cisco
+	  likes GRE much better than the other Linux tunneling driver ("IP
+	  tunneling" above). In addition, GRE allows multicast redistribution
+	  through the tunnel.
+
+	  Saying M here will produce a module called ip6_gre. If unsure, say N.
+
 config IPV6_MULTIPLE_TABLES
 	bool "IPv6: Multiple Routing Tables"
 	depends on EXPERIMENTAL