From patchwork Tue Aug 27 09:08:27 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yi Wang X-Patchwork-Id: 1153668 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=zte.com.cn Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 46HjkD6mY5z9sBp for ; Tue, 27 Aug 2019 19:09:40 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729010AbfH0JJe (ORCPT ); Tue, 27 Aug 2019 05:09:34 -0400 Received: from out1.zte.com.cn ([202.103.147.172]:48442 "EHLO mxct.zte.com.cn" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725805AbfH0JJe (ORCPT ); Tue, 27 Aug 2019 05:09:34 -0400 Received: from mse-fl1.zte.com.cn (unknown [10.30.14.238]) by Forcepoint Email with ESMTPS id CA0093140B52B6C1B3F1; Tue, 27 Aug 2019 17:09:27 +0800 (CST) Received: from notes_smtp.zte.com.cn (notes_smtp.zte.com.cn [10.30.1.239]) by mse-fl1.zte.com.cn with ESMTP id x7R984kp047150; Tue, 27 Aug 2019 17:08:04 +0800 (GMT-8) (envelope-from wang.yi59@zte.com.cn) Received: from fox-host8.localdomain ([10.74.120.8]) by szsmtp06.zte.com.cn (Lotus Domino Release 8.5.3FP6) with ESMTP id 2019082717081800-3205352 ; Tue, 27 Aug 2019 17:08:18 +0800 From: Yi Wang To: davem@davemloft.net Cc: kuznet@ms2.inr.ac.ru, yoshfuji@linux-ipv6.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, xue.zhihong@zte.com.cn, wang.yi59@zte.com.cn, wang.liang82@zte.com.cn, Cheng Lin Subject: [PATCH] ipv6: Not to probe neighbourless routes Date: Tue, 27 Aug 2019 17:08:27 +0800 Message-Id: <1566896907-5121-1-git-send-email-wang.yi59@zte.com.cn> X-Mailer: git-send-email 1.8.3.1 X-MIMETrack: Itemize by SMTP Server on SZSMTP06/server/zte_ltd(Release 8.5.3FP6|November 21, 2013) at 2019-08-27 17:08:18, Serialize by Router on notes_smtp/zte_ltd(Release 9.0.1FP7|August 17, 2016) at 2019-08-27 17:08:07, Serialize complete at 2019-08-27 17:08:07 X-MAIL: mse-fl1.zte.com.cn x7R984kp047150 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Cheng Lin Originally, Router Reachability Probing require a neighbour entry existed. Commit 2152caea7196 ("ipv6: Do not depend on rt->n in rt6_probe().") removed the requirement for a neighbour entry. And commit f547fac624be ("ipv6: rate-limit probes for neighbourless routes") adds rate-limiting for neighbourless routes. And, the Neighbor Discovery for IP version 6 (IPv6)(rfc4861) says, " 7.2.5. Receipt of Neighbor Advertisements When a valid Neighbor Advertisement is received (either solicited or unsolicited), the Neighbor Cache is searched for the target's entry. If no entry exists, the advertisement SHOULD be silently discarded. There is no need to create an entry if none exists, since the recipient has apparently not initiated any communication with the target. ". In rt6_probe(), just a Neighbor Solicitation message are transmited. When receiving a Neighbor Advertisement, the node does nothing in a Neighborless condition. Not sure it's needed to create a neighbor entry in Router Reachability Probing. And the Original way may be the right way. This patch recover the requirement for a neighbour entry. Signed-off-by: Cheng Lin --- include/net/ip6_fib.h | 5 ----- net/ipv6/route.c | 5 +---- 2 files changed, 1 insertion(+), 9 deletions(-) diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h index 4b5656c..8c2e022 100644 --- a/include/net/ip6_fib.h +++ b/include/net/ip6_fib.h @@ -124,11 +124,6 @@ struct rt6_exception { struct fib6_nh { struct fib_nh_common nh_common; - -#ifdef CONFIG_IPV6_ROUTER_PREF - unsigned long last_probe; -#endif - struct rt6_info * __percpu *rt6i_pcpu; struct rt6_exception_bucket __rcu *rt6i_exception_bucket; }; diff --git a/net/ipv6/route.c b/net/ipv6/route.c index fd059e0..c4bcffc 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -639,12 +639,12 @@ static void rt6_probe(struct fib6_nh *fib6_nh) nh_gw = &fib6_nh->fib_nh_gw6; dev = fib6_nh->fib_nh_dev; rcu_read_lock_bh(); - idev = __in6_dev_get(dev); neigh = __ipv6_neigh_lookup_noref(dev, nh_gw); if (neigh) { if (neigh->nud_state & NUD_VALID) goto out; + idev = __in6_dev_get(dev); write_lock(&neigh->lock); if (!(neigh->nud_state & NUD_VALID) && time_after(jiffies, @@ -654,9 +654,6 @@ static void rt6_probe(struct fib6_nh *fib6_nh) __neigh_set_probe_once(neigh); } write_unlock(&neigh->lock); - } else if (time_after(jiffies, fib6_nh->last_probe + - idev->cnf.rtr_probe_interval)) { - work = kmalloc(sizeof(*work), GFP_ATOMIC); } if (work) {