From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Pirko Subject: Re: [PATCH] team: set IFF_SLAVE on team ports Date: Tue, 2 Oct 2018 13:12:15 +0200 Message-ID: <20181002111215.GA2222@nanopsycho> References: <1436435914-8903-1-git-send-email-jblunck@infradead.org> <20150709100727.GE2270@nanopsycho.orion> <20150710064147.GA2204@nanopsycho.orion> <20180930071414.GF2209@nanopsycho.orion> <20180930113805.3b8e62a1@shemminger-XPS-13-9360> <20180930093452.GG2209@nanopsycho.orion> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Stephen Hemminger , Jan Blunck , LKML , netdev@vger.kernel.org To: Chas Williams <3chas3@gmail.com> Return-path: Received: from mail-wr1-f67.google.com ([209.85.221.67]:45214 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727244AbeJBSAL (ORCPT ); Tue, 2 Oct 2018 14:00:11 -0400 Received: by mail-wr1-f67.google.com with SMTP id q5-v6so1714889wrw.12 for ; Tue, 02 Oct 2018 04:17:23 -0700 (PDT) Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: Mon, Oct 01, 2018 at 04:06:16PM CEST, 3chas3@gmail.com wrote: > > >On 09/30/18 05:34, Jiri Pirko wrote: >> Sun, Sep 30, 2018 at 11:38:05AM CEST, stephen@networkplumber.org wrote: >> > On Sun, 30 Sep 2018 09:14:14 +0200 >> > Jiri Pirko wrote: >> > >> > > Thu, Sep 27, 2018 at 04:04:26PM CEST, 3chas3@gmail.com wrote: >> > > > >> > > > >> > > > On 07/10/15 02:41, Jiri Pirko wrote: >> > > > > Thu, Jul 09, 2015 at 05:36:55PM CEST, jblunck@infradead.org wrote: >> > > > > > On Thu, Jul 9, 2015 at 12:07 PM, Jiri Pirko wrote: >> > > > > > > Thu, Jul 09, 2015 at 11:58:34AM CEST, jblunck@infradead.org wrote: >> > > > > > > > The code in net/ipv6/addrconf.c:addrconf_notify() tests for IFF_SLAVE to >> > > > > > > > decide if it should start the address configuration. Since team ports >> > > > > > > > shouldn't get link-local addresses assigned lets set IFF_SLAVE when linking >> > > > > > > > a port to the team master. >> > > > > > > >> > > > > > > I don't want to use IFF_SLAVE in team. Other master-slave devices are >> > > > > > > not using that as well, for example bridge, ovs, etc. >> > > > > > >> > > > > > Maybe they need to get fixed too. I've used that flag because it is >> > > > > > documented as >> > > > > > a "slave of a load balancer" which describes what a team port is. >> > > > > > >> > > > > > > I think that this should be fixed in addrconf_notify. It should lookup >> > > > > > > if there is a master on top and bail out in that case. >> > > > > > >> > > > > > There are other virtual interfaces that have a master assigned and want to >> > > > > > participate in IPv6 address configuration. >> > > > > >> > > > > Can you give me an example? >> > > > >> > > > I would like to revisit this patch (yes, I know it has been a while). I >> > > > believe the VRF implementation uses master to group the interfaces under >> > > > a single interface. >> > > > >> > > > I don't see a reason not to use IFF_SLAVE since team and bonding are fairly >> > > > similar. >> > > >> > > Again, why do you need team port to have IFF_SLAVE flag? What do you >> > > want to achieve >> > >> > Without setting this flag IPv6 will try and make a link specific address. You are talking about addrconf_notify() right? Easy to fix to check something more convenient. Like netif_is_lag_port() if you want to avoid it for bond/team. netif_is_ovs_port(), netif_is_bridge_port() etc. Lot's of helpers to cover this. >> >> Why is it not an issue with bridge, ovs, and other master-slave devices? >> > >It very well might be an issue for bridge and ovs. Other master-slave >devices include the existing VRF implementation in the kernel and those slave >interfaces will certainly want to use IPv6. > >However, IFF_SLAVE has a specific meaning: > >./include/uapi/linux/if.h: * @IFF_SLAVE: slave of a load balancer. Volatile. I know that some userspace apps are using this flag to determine a "bonding slave". I don't think that they care much about eql... > >The bonding driver is not the only user: > >./drivers/net/eql.c:#define eql_is_slave(dev) ((dev->flags & IFF_SLAVE) == >IFF_SLAVE) >./drivers/net/eql.c: slave->dev->flags &= ~IFF_SLAVE; >./drivers/net/eql.c: slave->dev->flags |= IFF_SLAVE; > >The team driver would like to use this same flag since it is a load balancer >as well. The side effect of not assigning IPv6 is a bonus. The fact that No, please leave IFF_SLAVE as it is. Both kernel and userspace have their clear indications right now about the master/slave relationships. >bridges and ovs are also likely broken is a different issue. Should there be >a another flag that says "layer 2 only"? Very possibly, but that is >something all these interfaces should be using to include bonding, team, eql, >obs, bridge etc. That's not a reasonable objection to labeling the team >slave as slaves since they are literally slaves of a load balancer. > > >