From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:53480 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751015AbdEaARI (ORCPT ); Tue, 30 May 2017 20:17:08 -0400 Subject: Patch "vlan: Fix tcp checksum offloads in Q-in-Q vlans" has been added to the 4.11-stable tree To: vyasevich@gmail.com, davem@davemloft.net, gregkh@linuxfoundation.org, makita.toshiaki@lab.ntt.co.jp, mkubecek@suse.cz, vyasevic@redhat.com Cc: , From: Date: Wed, 31 May 2017 09:14:32 +0900 Message-ID: <149618967252118@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled vlan: Fix tcp checksum offloads in Q-in-Q vlans to the 4.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: vlan-fix-tcp-checksum-offloads-in-q-in-q-vlans.patch and it can be found in the queue-4.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Wed May 31 09:13:10 JST 2017 From: Vlad Yasevich Date: Tue, 23 May 2017 13:38:41 -0400 Subject: vlan: Fix tcp checksum offloads in Q-in-Q vlans From: Vlad Yasevich [ Upstream commit 35d2f80b07bbe03fb358afb0bdeff7437a7d67ff ] It appears that TCP checksum offloading has been broken for Q-in-Q vlans. The behavior was execerbated by the series commit afb0bc972b52 ("Merge branch 'stacked_vlan_tso'") that that enabled accleleration features on stacked vlans. However, event without that series, it is possible to trigger this issue. It just requires a lot more specialized configuration. The root cause is the interaction between how netdev_intersect_features() works, the features actually set on the vlan devices and HW having the ability to run checksum with longer headers. The issue starts when netdev_interesect_features() replaces NETIF_F_HW_CSUM with a combination of NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM, if the HW advertises IP|IPV6 specific checksums. This happens for tagged and multi-tagged packets. However, HW that enables IP|IPV6 checksum offloading doesn't gurantee that packets with arbitrarily long headers can be checksummed. This patch disables IP|IPV6 checksums on the packet for multi-tagged packets. CC: Toshiaki Makita CC: Michal Kubecek Signed-off-by: Vladislav Yasevich Acked-by: Toshiaki Makita Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/linux/if_vlan.h | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) --- a/include/linux/if_vlan.h +++ b/include/linux/if_vlan.h @@ -614,14 +614,16 @@ static inline bool skb_vlan_tagged_multi static inline netdev_features_t vlan_features_check(const struct sk_buff *skb, netdev_features_t features) { - if (skb_vlan_tagged_multi(skb)) - features = netdev_intersect_features(features, - NETIF_F_SG | - NETIF_F_HIGHDMA | - NETIF_F_FRAGLIST | - NETIF_F_HW_CSUM | - NETIF_F_HW_VLAN_CTAG_TX | - NETIF_F_HW_VLAN_STAG_TX); + if (skb_vlan_tagged_multi(skb)) { + /* In the case of multi-tagged packets, use a direct mask + * instead of using netdev_interesect_features(), to make + * sure that only devices supporting NETIF_F_HW_CSUM will + * have checksum offloading support. + */ + features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_HW_CSUM | + NETIF_F_FRAGLIST | NETIF_F_HW_VLAN_CTAG_TX | + NETIF_F_HW_VLAN_STAG_TX; + } return features; } Patches currently in stable-queue which might be from vyasevich@gmail.com are queue-4.11/vlan-fix-tcp-checksum-offloads-in-q-in-q-vlans.patch queue-4.11/be2net-fix-offload-features-for-q-in-q-packets.patch queue-4.11/virtio-net-enable-tso-checksum-offloads-for-q-in-q-vlans.patch queue-4.11/sctp-fix-icmp-processing-if-skb-is-non-linear.patch