From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Frederic Sowa Subject: Re: [PATCH] net: Fix tentative IPv6 address due to DAD looping back Date: Fri, 12 Apr 2013 22:03:53 +0200 Message-ID: <20130412200353.GA23992@order.stressinduktion.org> References: <027526AF93736D4380632CD4F3B42B80030B85@MX101CL02.corp.emc.com> <20130412175141.GA30292@order.stressinduktion.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 To: "Meng, Jilin" , "davem@davemloft.net" , "kuznet@ms2.inr.ac.ru" , "jmorris@namei.org" , "yoshfuji@linux-ipv6.org" , "kaber@trash.net" , "Sun, Yinglin" , "Prithviraj, Lakshmanan" , "netdev@vger.kernel.org" , Eric Dumazet Return-path: Received: from order.stressinduktion.org ([87.106.68.36]:40701 "EHLO order.stressinduktion.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752909Ab3DLUDz (ORCPT ); Fri, 12 Apr 2013 16:03:55 -0400 Content-Disposition: inline In-Reply-To: <20130412175141.GA30292@order.stressinduktion.org> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, Apr 12, 2013 at 07:51:41PM +0200, Hannes Frederic Sowa wrote: > On Fri, Apr 12, 2013 at 07:45:54AM +0000, Meng, Jilin wrote: > > This version accepted David's comments of coding style, Eric's comments of ether_addr_equal_64bits(), and Hannes' comments of eth_hdr(), etc. > > > > we should ignore the looped-back IPv6 DAD packet to avoid configuration failure. > > This occurs when a bonding interface with roundrobin mode is being configured an IPv6 address while the switch side isn't configured bonding/channel yet. > [...] > What do you think if we hook up a function which does reenable ipv6 on > an interface as soon as 'disable_ipv6' is switched to '0'? So you could > control reacquiring the ipv6 address from userspace without ifup&ifdown > and the risk of disturbing ipv4 connections? This seems to be the > easiest solution (but have not checked thoroughly). > [...] I just looked into it and it does already worked as expected. Didn't know why I assumed that there was only a disable handler. So you can resolve this issue from userspace by a timer or a small program which listens for loopback traffic in userspace and do DAD after the loop is resolved. I think this is a more sensible solution. Thanks, Hannes