From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm@xmission.com (Eric W. Biederman) Subject: Re: [RFC PATCH net-next 0/5] netns: allow to identify peer netns Date: Wed, 02 Jul 2014 13:09:58 -0700 Message-ID: <87simj7ca1.fsf@x220.int.ebiederm.org> References: <537327F1.4060603@6wind.com> <1404302346-4507-1-git-send-email-nicolas.dichtel@6wind.com> Mime-Version: 1.0 Content-Type: text/plain Cc: netdev@vger.kernel.org, davem@davemloft.net, stephen@networkplumber.org To: Nicolas Dichtel Return-path: Received: from out03.mta.xmission.com ([166.70.13.233]:43219 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752704AbaGBUNX (ORCPT ); Wed, 2 Jul 2014 16:13:23 -0400 In-Reply-To: <1404302346-4507-1-git-send-email-nicolas.dichtel@6wind.com> (Nicolas Dichtel's message of "Wed, 2 Jul 2014 13:59:01 +0200") Sender: netdev-owner@vger.kernel.org List-ID: Nicolas Dichtel writes: > The goal of this serie is to be able to multicast netlink messages with an > attribute that identify a peer netns. > This is needed by the userland to interpret some informations contained in > netlink messages (like IFLA_LINK value, but also some other attributes in case > of x-netns netdevice (see also > http://thread.gmane.org/gmane.linux.network/315933/focus=316064)). > > Each network namespaces allocates its own ids for other netns (including > itself). The user can retrieve these ids via a new netlink messages, but only > if he has a FD which points to this netns. Dump is not implemented so that a > user cannot get the whole netns list. > > The goal of this RFC is mainly to validate the principle, ie patch 1/5 and 2/5. > Patch 3/5 and 4/5 shows an example of how to use these ids in rtnetlink > messages. And patch 5/5 shows that the netlink messages can be symetric between > a GET and a SET. This approach fundamentally breaks process migration, and calls for a namespace of namespaces. Which means this is a major mess that really isn't going to work because it generates more problems than it solves. Eric