| Message ID | 1387204283.19078.240.camel@edumazet-glaptop2.roam.corp.google.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On 12/16/2013 03:31 PM, Eric Dumazet wrote: > From: Eric Dumazet <edumazet@google.com> > > While testing my changes for TSO support in SIT devices, > I was using sit0 tunnel which appears to include nopmtudisc flag. > > But using : > > ip tun add sittun mode sit remote $REMOTE_IPV4 local $LOCAL_IPV4 \ > dev $IFACE > > We get a tunnel which rejects too long packets because of the mtu check > which is not yet GSO aware. > > erd:~# ip tunnel > sittun: ipv6/ip remote 10.246.17.84 local 10.246.17.83 ttl inherit 6rd-prefix 2002::/16 > sit0: ipv6/ip remote any local any ttl 64 nopmtudisc 6rd-prefix 2002::/16 > > This patch is based on an excellent report from > Michal Shmidt. > > In the future, we probably want to extend the MTU check to do the > right thing for GSO packets... > > Fixes: ("61c1db7fae21 ipv6: sit: add GSO/TSO support") > Reported-by: Michal Schmidt <mschmidt@redhat.com> > Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Michal Schmidt <mschmidt@redhat.com> It works fine now. Thanks. Michal -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, 2013-12-17 at 15:22 +0100, Michal Schmidt wrote: > Tested-by: Michal Schmidt <mschmidt@redhat.com> > > It works fine now. Thanks. > Michal Thanks a lot Michal for your very nice bug report ! -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Eric! On Mon, Dec 16, 2013 at 06:31:23AM -0800, Eric Dumazet wrote: > In the future, we probably want to extend the MTU check to do the > right thing for GSO packets... How could that look like? Greetings, Hannes -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, 2013-12-17 at 21:19 +0100, Hannes Frederic Sowa wrote: > Hi Eric! > > On Mon, Dec 16, 2013 at 06:31:23AM -0800, Eric Dumazet wrote: > > In the future, we probably want to extend the MTU check to do the > > right thing for GSO packets... > > How could that look like? I think I already posted a draft for this. Idea would be to have a helper to compute the mtu of each segment : static inline unsigned int gso_size_with_headers(const struct sk_buff *skb) { unsigned int hdrlen = skb_transport_header(skb) - skb_network_header(skb); if (skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)) hdrlen += tcp_hdrlen(skb); else hdrlen += 8; // sizeof(struct udphdr) return skb_shinfo(skb)->gso_size + hdrlen; } ... len = skb_is_gso(skb) ? gso_size_with_headers(skb) : skb->len; if (unlikely(len > dst_mtu(&rt->dst) && ... -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Eric Dumazet <eric.dumazet@gmail.com> Date: Mon, 16 Dec 2013 06:31:23 -0800 > From: Eric Dumazet <edumazet@google.com> > > While testing my changes for TSO support in SIT devices, > I was using sit0 tunnel which appears to include nopmtudisc flag. > > But using : > > ip tun add sittun mode sit remote $REMOTE_IPV4 local $LOCAL_IPV4 \ > dev $IFACE > > We get a tunnel which rejects too long packets because of the mtu check > which is not yet GSO aware. > > erd:~# ip tunnel > sittun: ipv6/ip remote 10.246.17.84 local 10.246.17.83 ttl inherit 6rd-prefix 2002::/16 > sit0: ipv6/ip remote any local any ttl 64 nopmtudisc 6rd-prefix 2002::/16 > > This patch is based on an excellent report from > Michal Shmidt. > > In the future, we probably want to extend the MTU check to do the > right thing for GSO packets... > > Fixes: ("61c1db7fae21 ipv6: sit: add GSO/TSO support") > Reported-by: Michal Schmidt <mschmidt@redhat.com> > Signed-off-by: Eric Dumazet <edumazet@google.com> Applied, thanks Eric. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index 366fbba3359a..a710fdec42d3 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -924,7 +924,7 @@ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, if (tunnel->parms.iph.daddr && skb_dst(skb)) skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); - if (skb->len > mtu) { + if (skb->len > mtu && !skb_is_gso(skb)) { icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); ip_rt_put(rt); goto tx_error;