From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:57897 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933425AbcFQSSt (ORCPT ); Fri, 17 Jun 2016 14:18:49 -0400 Subject: Patch "vxlan: Relax MTU constraints" has been added to the 4.4-stable tree To: david@weave.works, davem@davemloft.net, gregkh@linuxfoundation.org, roopa@cumulusnetworks.com Cc: , From: Date: Fri, 17 Jun 2016 11:18:48 -0700 Message-ID: <146618752721165@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 vxlan: Relax MTU constraints to the 4.4-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: vxlan-relax-mtu-constraints.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Fri Jun 17 11:18:18 PDT 2016 From: David Wragg Date: Fri, 3 Jun 2016 18:58:13 -0400 Subject: vxlan: Relax MTU constraints From: David Wragg [ Upstream commit 72564b59ffc438ea103b0727a921aaddce766728 ] Allow the MTU of vxlan devices without an underlying device to be set to larger values (up to a maximum based on IP packet limits and vxlan overhead). Previously, their MTUs could not be set to higher than the conventional ethernet value of 1500. This is a very arbitrary value in the context of vxlan, and prevented vxlan devices from being able to take advantage of jumbo frames etc. The default MTU remains 1500, for compatibility. Signed-off-by: David Wragg Acked-by: Roopa Prabhu Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/vxlan.c | 36 +++++++++++++++++++++++++----------- 1 file changed, 25 insertions(+), 11 deletions(-) --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -2364,29 +2364,43 @@ static void vxlan_set_multicast_list(str { } -static int vxlan_change_mtu(struct net_device *dev, int new_mtu) +static int __vxlan_change_mtu(struct net_device *dev, + struct net_device *lowerdev, + struct vxlan_rdst *dst, int new_mtu, bool strict) { - struct vxlan_dev *vxlan = netdev_priv(dev); - struct vxlan_rdst *dst = &vxlan->default_dst; - struct net_device *lowerdev; - int max_mtu; + int max_mtu = IP_MAX_MTU; - lowerdev = __dev_get_by_index(vxlan->net, dst->remote_ifindex); - if (lowerdev == NULL) - return eth_change_mtu(dev, new_mtu); + if (lowerdev) + max_mtu = lowerdev->mtu; if (dst->remote_ip.sa.sa_family == AF_INET6) - max_mtu = lowerdev->mtu - VXLAN6_HEADROOM; + max_mtu -= VXLAN6_HEADROOM; else - max_mtu = lowerdev->mtu - VXLAN_HEADROOM; + max_mtu -= VXLAN_HEADROOM; - if (new_mtu < 68 || new_mtu > max_mtu) + if (new_mtu < 68) return -EINVAL; + if (new_mtu > max_mtu) { + if (strict) + return -EINVAL; + + new_mtu = max_mtu; + } + dev->mtu = new_mtu; return 0; } +static int vxlan_change_mtu(struct net_device *dev, int new_mtu) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + struct vxlan_rdst *dst = &vxlan->default_dst; + struct net_device *lowerdev = __dev_get_by_index(vxlan->net, + dst->remote_ifindex); + return __vxlan_change_mtu(dev, lowerdev, dst, new_mtu, true); +} + static int egress_ipv4_tun_info(struct net_device *dev, struct sk_buff *skb, struct ip_tunnel_info *info, __be16 sport, __be16 dport) Patches currently in stable-queue which might be from david@weave.works are queue-4.4/geneve-relax-mtu-constraints.patch queue-4.4/vxlan-relax-mtu-constraints.patch queue-4.4/vxlan-gre-geneve-set-a-large-mtu-on-ovs-created-tunnel-devices.patch