Re: tunnels: Don't apply GRO to multiple layers of encapsulation.

[joe.korty@concurrent-rt.com]

Hi Sasha,
The backport of

   fac8e0f579695a3ecbc4d3cac369139d7f819971
   tunnels: Don't apply GRO to multiple layers of encapsulation

into 4.1 missed a hunk.  The same backport into 3.18 was done
correctly.  This patch introduces the missing hunk into 4.1.
Excepts from some emails:

Joe Korty wrote:
> I am not experiencing any bad symptoms.  I simply noticed
> that the patch introduced a new function, sit_gro_receive,
> without introducing any users, and that same patch in
> linux-4.4.y does have a user.

Jesse gross wrote:
> Thanks for pointing that out. The line you mentioned
> should indeed be there and seems to have been missed in
> the backport.
> 
> The backport was actually done by Sasha, not by me -
> would you mind sending a patch to him or working with him
> to fix it?

Could you review this and run it through your tests and
send it along to Greg if appropriate?

Thanks,
Joe

Signed-off-by: Joe Korty <joe.korty@concurrent-rt.com>

Index: b/net/ipv6/ip6_offload.c
===================================================================
--- a/net/ipv6/ip6_offload.c
+++ b/net/ipv6/ip6_offload.c
@@ -300,7 +300,7 @@ static struct packet_offload ipv6_packet
 	.type = cpu_to_be16(ETH_P_IPV6),
 	.callbacks = {
 		.gso_segment = ipv6_gso_segment,
-		.gro_receive = ipv6_gro_receive,
+		.gro_receive = sit_gro_receive,
 		.gro_complete = ipv6_gro_complete,
 	},
 };