From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net] net: try harder to not reuse ifindex when moving interfaces Date: Wed, 21 Oct 2015 08:32:14 -0700 (PDT) Message-ID: <20151021.083214.534622235927401863.davem@davemloft.net> References: <294c7a9df554506e684adbeb9bbed070e6fed260.1444993627.git.jbenc@redhat.com> <20151021.074332.1709904332480699231.davem@davemloft.net> <20151021164613.24650836@griffin> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, thaller@redhat.com To: jbenc@redhat.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:44959 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755677AbbJUPPs (ORCPT ); Wed, 21 Oct 2015 11:15:48 -0400 In-Reply-To: <20151021164613.24650836@griffin> Sender: netdev-owner@vger.kernel.org List-ID: From: Jiri Benc Date: Wed, 21 Oct 2015 16:46:13 +0200 > For example, we could always alloc a new ifindex when moving interfaces > between name spaces. That would be probably the tiniest race window we > could get to (still not zero!) but I guess it would break apps that > assume that ifindex doesn't change when moving interfaces between name > spaces (which is not true, such apps are already broken, they just > happen to work in 99% of cases). The second best solution that doesn't > break those apps at the cost of leaving the race window wider, is this > patch. As you say the apps are broken, so file a bug and have them fixed. The assumption is clearly invalid, so apps cannot make such an assumption.