From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC2B7C4CEC9 for ; Fri, 20 Sep 2019 14:32:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9D51C2080F for ; Fri, 20 Sep 2019 14:32:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389441AbfITOcc (ORCPT ); Fri, 20 Sep 2019 10:32:32 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:36498 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388283AbfITOZK (ORCPT ); Fri, 20 Sep 2019 10:25:10 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1iBJqN-000514-G2; Fri, 20 Sep 2019 15:25:07 +0100 Received: from ben by deadeye with local (Exim 4.92.1) (envelope-from ) id 1iBJqG-0007wH-CX; Fri, 20 Sep 2019 15:25:00 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , netdev@vger.kernel.org, "David S. Miller" , "Veaceslav Falico" , "Jarod Wilson" , "Jay Vosburgh" , "Andy Gospodarek" , "Jay Vosburgh" Date: Fri, 20 Sep 2019 15:23:35 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 095/132] bonding: fix arp_validate toggling in active-backup mode In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 3.16.74-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Jarod Wilson commit a9b8a2b39ce65df45687cf9ef648885c2a99fe75 upstream. There's currently a problem with toggling arp_validate on and off with an active-backup bond. At the moment, you can start up a bond, like so: modprobe bonding mode=1 arp_interval=100 arp_validate=0 arp_ip_targets=192.168.1.1 ip link set bond0 down echo "ens4f0" > /sys/class/net/bond0/bonding/slaves echo "ens4f1" > /sys/class/net/bond0/bonding/slaves ip link set bond0 up ip addr add 192.168.1.2/24 dev bond0 Pings to 192.168.1.1 work just fine. Now turn on arp_validate: echo 1 > /sys/class/net/bond0/bonding/arp_validate Pings to 192.168.1.1 continue to work just fine. Now when you go to turn arp_validate off again, the link falls flat on it's face: echo 0 > /sys/class/net/bond0/bonding/arp_validate dmesg ... [133191.911987] bond0: Setting arp_validate to none (0) [133194.257793] bond0: bond_should_notify_peers: slave ens4f0 [133194.258031] bond0: link status definitely down for interface ens4f0, disabling it [133194.259000] bond0: making interface ens4f1 the new active one [133197.330130] bond0: link status definitely down for interface ens4f1, disabling it [133197.331191] bond0: now running without any active interface! The problem lies in bond_options.c, where passing in arp_validate=0 results in bond->recv_probe getting set to NULL. This flies directly in the face of commit 3fe68df97c7f, which says we need to set recv_probe = bond_arp_recv, even if we're not using arp_validate. Said commit fixed this in bond_option_arp_interval_set, but missed that we can get to that same state in bond_option_arp_validate_set as well. One solution would be to universally set recv_probe = bond_arp_recv here as well, but I don't think bond_option_arp_validate_set has any business touching recv_probe at all, and that should be left to the arp_interval code, so we can just make things much tidier here. Fixes: 3fe68df97c7f ("bonding: always set recv_probe to bond_arp_rcv in arp monitor") CC: Jay Vosburgh CC: Veaceslav Falico CC: Andy Gospodarek CC: "David S. Miller" CC: netdev@vger.kernel.org Signed-off-by: Jarod Wilson Signed-off-by: Jay Vosburgh Signed-off-by: David S. Miller [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- drivers/net/bonding/bond_options.c | 7 ------- 1 file changed, 7 deletions(-) --- a/drivers/net/bonding/bond_options.c +++ b/drivers/net/bonding/bond_options.c @@ -1068,13 +1068,6 @@ static int bond_option_arp_validate_set( { pr_info("%s: Setting arp_validate to %s (%llu)\n", bond->dev->name, newval->string, newval->value); - - if (bond->dev->flags & IFF_UP) { - if (!newval->value) - bond->recv_probe = NULL; - else if (bond->params.arp_interval) - bond->recv_probe = bond_arp_rcv; - } bond->params.arp_validate = newval->value; return 0;