From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: FW: PROBLEM: VLAN LRO issue
Date: Thu, 10 May 2012 03:25:47 +0200
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To: Steven Liu =?UTF-8?Q?=28=E5=8A=89=E4=BA=BA=E8=B1=AA=29?=
	<steven.liu@mediatek.com>
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On Thu, 2012-05-10 at 09:01 +0800, Steven Liu (=E5=8A=89=E4=BA=BA=E8=B1=
=AA) wrote:
> Hi Sir,
>=20
> I found the issue about VLAN LRO feature and below is bug description=
 and patch for your reference, thanks.
>=20
> [1.] One line summary of the problem:=20
> VLAN LRO issue
>=20
> [2.] Full description of the problem/report:
> LRO implementation cannot handle VLAN tagged packets correctly.
> It uses correct packet length when creating new LRO session, but uses=
 wrong packet length when putting following packets into exist LRO sess=
ion.
>=20
> [3.] Keywords (i.e., modules, networking, kernel):
> Networking
>=20
> [4.] Kernel version (from /proc/version):
> Linux-3.4-rc3 and below
>=20
> [5.] Output of Oops.. message (if applicable) with symbolic informati=
on
>      resolved (see Documentation/oops-tracing.txt) System is still wo=
rking, but cannot speed up VLAN tagged traffic.
>=20
> [X.] Other notes, patches, fixes, workarounds:
> We have to apply below patch to fix this issue.
>=20
> --- linux-3.4-rc3/net/ipv4/inet_lro.orig        2012-05-08 20:09:44.8=
10366089 +0800
> +++ linux-3.4-rc3/net/ipv4/inet_lro.c   2012-05-08 20:09:33.331679419=
 +0800
> @@ -353,7 +353,7 @@ static int __lro_proc_skb(struct net_lro
>         if (lro_desc->tcp_next_seq !=3D ntohl(tcph->seq))
>                 goto out2;
>=20
> -       if (lro_tcp_ip_check(iph, tcph, skb->len, lro_desc))
> +       if (lro_tcp_ip_check(iph, tcph, skb->len - vlan_hdr_len, lro_=
desc))
>                 goto out2;
>=20
>         lro_add_packet(lro_desc, skb, iph, tcph);
>=20

Hi=20

This looks like a good fix, could you please submit an official patch ?

Documentation/SubmittingPatches