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=-6.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 1DC88C04A6B for ; Fri, 10 May 2019 21:57:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E6554217D6 for ; Fri, 10 May 2019 21:57:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728287AbfEJV5k (ORCPT ); Fri, 10 May 2019 17:57:40 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43302 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727828AbfEJV5j (ORCPT ); Fri, 10 May 2019 17:57:39 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5F87C307D913; Fri, 10 May 2019 21:57:39 +0000 (UTC) Received: from hp-dl360pgen8-07.khw2.lab.eng.bos.redhat.com (hp-dl360pgen8-07.khw2.lab.eng.bos.redhat.com [10.16.210.135]) by smtp.corp.redhat.com (Postfix) with ESMTP id C82941A267; Fri, 10 May 2019 21:57:35 +0000 (UTC) From: Jarod Wilson To: linux-kernel@vger.kernel.org Cc: Jarod Wilson , Jay Vosburgh , Veaceslav Falico , Andy Gospodarek , "David S. Miller" , netdev@vger.kernel.org Subject: [PATCH] bonding: fix arp_validate toggling in active-backup mode Date: Fri, 10 May 2019 17:57:09 -0400 Message-Id: <20190510215709.19162-1-jarod@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.48]); Fri, 10 May 2019 21:57:39 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- drivers/net/bonding/bond_options.c | 7 ------- 1 file changed, 7 deletions(-) diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c index da1fc17295d9..b996967af8d9 100644 --- a/drivers/net/bonding/bond_options.c +++ b/drivers/net/bonding/bond_options.c @@ -1098,13 +1098,6 @@ static int bond_option_arp_validate_set(struct bonding *bond, { netdev_dbg(bond->dev, "Setting arp_validate to %s (%llu)\n", 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; -- 2.20.1