From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f175.google.com ([209.85.192.175]:45026 "EHLO mail-pf0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932337AbeCEBL3 (ORCPT ); Sun, 4 Mar 2018 20:11:29 -0500 Received: by mail-pf0-f175.google.com with SMTP id 17so6515383pfw.11 for ; Sun, 04 Mar 2018 17:11:29 -0800 (PST) Subject: Re: [PATCH net] ipv6: Reflect MTU changes on PMTU of exceptions for MTU-less routes To: Stefano Brivio Cc: "David S . Miller" , Wei Wang , Hideaki YOSHIFUJI , =?UTF-8?Q?Maciej_=c5=bbenczykowski?= , netdev@vger.kernel.org References: <81bfe26bed31319d765a4ebfe86705a49c0a39d5.1520003901.git.sbrivio@redhat.com> <84593e49-357b-818c-79c5-d265d8c32b03@gmail.com> <20180303122236.6dde3a9b@epycfail> <20180305001245.23b56b3f@epycfail> From: David Ahern Message-ID: Date: Sun, 4 Mar 2018 18:11:41 -0700 MIME-Version: 1.0 In-Reply-To: <20180305001245.23b56b3f@epycfail> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org List-ID: On 3/4/18 4:12 PM, Stefano Brivio wrote: > On Sat, 3 Mar 2018 12:22:36 +0100 > Stefano Brivio wrote: > >>> And please codify the above expectation as a test under >>> tools/testing/selftests/net >> >> And this, along with v2. > > On a second thought: I start thinking it doesn't make much sense, > especially given the current context of self-tests, to explicitly test > this, because it's a rather particular corner case. > > I think it would make more sense to introduce generic tests first. > About, say, PMTU, or route exceptions, but not "tunnel causes route > exception and administrative change doesn't affect PMTU". > I would argue corner cases in particular should be documented. >>From the commit message it seems like you took the time to create a test setup using network namespaces. Throw those commands into a shell script -- tools/testing/selftests/net/mtu.sh. It can evolve from there.