From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm@xmission.com (Eric W. Biederman) Subject: Re: [patch iproute2 1/6] iproute2: ipa: show switch id Date: Thu, 04 Dec 2014 15:24:13 -0600 Message-ID: <871tofun0i.fsf@x220.int.ebiederm.org> References: <87y4qne6if.fsf@x220.int.ebiederm.org> <20141204163024.GG1861@nanopsycho.orion> <87388v9ua6.fsf@x220.int.ebiederm.org> <20141204182451.GI1861@nanopsycho.orion> <87k327450a.fsf@x220.int.ebiederm.org> <20141204191926.GK1861@nanopsycho.orion> <87wq672p49.fsf@x220.int.ebiederm.org> <87h9xbxjrd.fsf@x220.int.ebiederm.org> <20141204202742.GM1861@nanopsycho.orion> <87388vw2xg.fsf@x220.int.ebiederm.org> <20141204211041.GN1861@nanopsycho.orion> Mime-Version: 1.0 Content-Type: text/plain Cc: netdev@vger.kernel.org, davem@davemloft.net, nhorman@tuxdriver.com, andy@greyhouse.net, tgraf@suug.ch, dborkman@redhat.com, ogerlitz@mellanox.com, jesse@nicira.com, pshelar@nicira.com, azhou@nicira.com, ben@decadent.org.uk, stephen@networkplumber.org, jeffrey.t.kirsher@intel.com, vyasevic@redhat.com, xiyou.wangcong@gmail.com, john.r.fastabend@intel.com, edumazet@google.com, jhs@mojatatu.com, sfeldma@gmail.com, f.fainelli@gmail.com, roopa@cumulusnetworks.com, linville@tuxdriver.com, jasowang@redhat.com, nicolas.dichtel@6wind.com, ryazanov.s.a@gmail.com, buytenh@wantstofly.org, aviadr@mellanox.com, nbd@openwrt.org, alexei.starovoitov@gmail.com, Neil.Jerram@metaswitch.com, ronye@mellanox.com, simon.horman@netronome.com, alexander.h.duyck@redhat.com, john.ronciak@intel.com, mleitner@redhat.com, shrijeet@gmail.com, gospo@cumulusnetworks.com, bcrl@kvack.org, hemal@broadcom.c To: Jiri Pirko Return-path: Received: from out02.mta.xmission.com ([166.70.13.232]:51442 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753106AbaLDV0h (ORCPT ); Thu, 4 Dec 2014 16:26:37 -0500 In-Reply-To: <20141204211041.GN1861@nanopsycho.orion> (Jiri Pirko's message of "Thu, 4 Dec 2014 22:10:41 +0100") Sender: netdev-owner@vger.kernel.org List-ID: Jiri Pirko writes: >>No. phys_port_id is not broken in the same way, and phys_port_id does >>not have the same set of properties. >> >>phys_port_id's in practice all have an IEEE prefix that identifies the >>manufacturer and a manufacture assigned serial number. Aka a mac >>address or a EUID-64. What the mlx4 ethernet driver is doing retunring >>a 64bit EUID-64 I don't know. If there are problems in the worst >>case issues with phys_port_id are fixable by simple driver tweaks, >>because fundamentally we are working with globally uniuqe identifiers. >>Well globally unique baring manufacturing bugs in eeproms. > > Well the fact that phys_post_id's are now implemented mostly by putting > mac into it does not mean that other drivers cannot do it differently. > So once again, phys_port_id and phys_switch_id are the same in this > matter. No exclusively implemented that way. And yes other drivers can implement bugs, that doesn't mean those bugs will be toleraged and won't break userspace. >>I agree with you that the switch id concept can be saved. But I think >>we should fix switch id before we export it to userspace so we don't >>have to break userspace later. >> >>My intuition says we want something like ifindex, but I am not at all >>certain how switch id is planned to be used. Given that it is single >>box I don't expect you are sending it out over the wire. > > No, it is not to be send out. > >> >>*shrug* >> >>Why does switch id need to be persistent? Why can't switch id be >>property like ifindex? > > Well I can imagine that multiple ports of the same switch chip could be > passed through to the virtual machines (similar to SR-IOV pf/vf). In that case you do need something that is globally unique. Because if I migrate your virtual machine onto a different physical machine seeing the same switch id and I might make the mistaken assumption that I am remain on the same switch if the ids are not global. >>What are the actual requirements. > > > They are actually very similar to phys_port_id. Therefore I made that > the same. Then please for rocket use a non-buggy implementation with a globally unique id. Given your descriptions of the requirements I can't see how any other implementation isn't buggy. Eric