From mboxrd@z Thu Jan 1 00:00:00 1970 From: zhuyj Subject: Should linux send netlink message as it is deleting that routing entry? Date: Thu, 10 Apr 2014 16:23:26 +0800 Message-ID: <534654FE.3040804@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit To: netdev@vger.kernel.org, "David S. Miller" , ebiederm@xmission.com, ja@ssi.bg, zhuyj , "Yang, Zhangle (Eric)" , "Tao, Yue" , "Zadoyan, Grant" Return-path: Received: from mail-pa0-f41.google.com ([209.85.220.41]:55751 "EHLO mail-pa0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965164AbaDJIX0 (ORCPT ); Thu, 10 Apr 2014 04:23:26 -0400 Received: by mail-pa0-f41.google.com with SMTP id fa1so3697450pad.28 for ; Thu, 10 Apr 2014 01:23:25 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-ID: Hi, David With ubuntu 12.04, I run the following to reproduce this defect. 1) Configure an interface ifconfig eth1 150.0.0.1/24 up 2) Add routing entry via that interface address route add -net 200.0.0.0/24 gw 150.0.0.1 3) Change the ip address on that interface as shown below. ifconfig eth1 151.0.0.1/24 up 4) Check netlink messages with "ip monitor all". There is no route delete netlink message. [ADDR]Deleted 3: eth1 inet 150.0.0.1/24 brd 150.0.0.255 scope global eth1 [ROUTE]Deleted 150.0.0.0/24 dev eth1 proto kernel scope link src 150.0.0.1 [ROUTE]Deleted broadcast 150.0.0.255 dev eth1 table local proto kernel scope link src 150.0.0.1 [ROUTE]Deleted broadcast 150.0.0.0 dev eth1 table local proto kernel scope link src 150.0.0.1 [ROUTE]Deleted local 150.0.0.1 dev eth1 table local proto kernel scope host src 150.0.0.1 [NEIGH]224.0.0.251 dev eth1 lladdr 01:00:5e:00:00:fb NOARP [NEIGH]224.0.0.22 dev eth1 lladdr 01:00:5e:00:00:16 NOARP [ADDR]3: eth1 inet 151.0.0.1/16 brd 151.0.255.255 scope global eth1 [ROUTE]local 151.0.0.1 dev eth1 table local proto kernel scope host src 151.0.0.1 [ROUTE]broadcast 151.0.255.255 dev eth1 table local proto kernel scope link src 151.0.0.1 [ROUTE]151.0.0.0/16 dev eth1 proto kernel scope link src 151.0.0.1 [ROUTE]broadcast 151.0.0.0 dev eth1 table local proto kernel scope link src 151.0.0.1 [ADDR]Deleted 3: eth1 inet 151.0.0.1/16 brd 151.0.255.255 scope global eth1 [ROUTE]Deleted 151.0.0.0/16 dev eth1 proto kernel scope link src 151.0.0.1 [ROUTE]Deleted broadcast 151.0.255.255 dev eth1 table local proto kernel scope link src 151.0.0.1 [ROUTE]Deleted broadcast 151.0.0.0 dev eth1 table local proto kernel scope link src 151.0.0.1 [ROUTE]Deleted local 151.0.0.1 dev eth1 table local proto kernel scope host src 151.0.0.1 [NEIGH]224.0.0.22 dev eth1 lladdr 01:00:5e:00:00:16 NOARP [ADDR]3: eth1 inet 151.0.0.1/24 brd 151.0.0.255 scope global eth1 [ROUTE]local 151.0.0.1 dev eth1 table local proto kernel scope host src 151.0.0.1 [ROUTE]broadcast 151.0.0.255 dev eth1 table local proto kernel scope link src 151.0.0.1 [ROUTE]151.0.0.0/24 dev eth1 proto kernel scope link src 151.0.0.1 [ROUTE]broadcast 151.0.0.0 dev eth1 table local proto kernel scope link src 151.0.0.1 There is no netlink message to notify that 200.0.0.0/24 is deleted. But in fact, this 200.0.0.0/24 route item disappears. I checked the source code, and I found the following is the process to delete static routes when the attached interface is deleted. 1) | fib_netdev_event() { 1) | fib_disable_ip() { 1) 1.284 us | fib_sync_down_dev(); 1) | fib_flush() { 1) | fib_table_flush() { 1) 0.129 us | fib_release_info(); 1) 0.351 us | fib_release_info(); 1) 4.605 us | } 1) | fib_table_flush() { 1) 0.096 us | fib_release_info(); 1) 0.255 us | fib_release_info(); 1) 4.770 us | } 1) + 11.787 us | } 1) ! 315.273 us | } 1) ! 315.888 us | } But there is no netlink message sent here. Should linux send netlink message as it is deleting that 200.0.0.0/24 routing entry? Best Regards! Zhu Yanjun