From owner-svn-src-all@FreeBSD.ORG Mon Jan 12 15:51:03 2015 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 1197FEC4; Mon, 12 Jan 2015 15:51:03 +0000 (UTC) Received: from bigwig.baldwin.cx (bigwig.baldwin.cx [IPv6:2001:470:1f11:75::1]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id D9BE9E29; Mon, 12 Jan 2015 15:51:02 +0000 (UTC) Received: from ralph.baldwin.cx (pool-173-70-85-31.nwrknj.fios.verizon.net [173.70.85.31]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 41256B94E; Mon, 12 Jan 2015 10:51:01 -0500 (EST) From: John Baldwin To: Bryan Venteicher Subject: Re: svn commit: r272886 - in head/sys: netinet netinet6 Date: Mon, 12 Jan 2015 10:51 -0500 Message-ID: <6173473.uE5Sr5nj0c@ralph.baldwin.cx> User-Agent: KMail/4.14.2 (FreeBSD/10.1-STABLE; KDE/4.14.2; amd64; ; ) In-Reply-To: References: <201410100609.s9A690NU067686@svn.freebsd.org> <54AC6F4E.1000707@FreeBSD.org> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (bigwig.baldwin.cx); Mon, 12 Jan 2015 10:51:01 -0500 (EST) Cc: "svn-src-head@freebsd.org" , "svn-src-all@freebsd.org" , "src-committers@freebsd.org" , John Nielsen , Bryan Drewery X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 12 Jan 2015 15:51:03 -0000 On Tuesday, January 06, 2015 07:07:11 PM Bryan Venteicher wrote: > On Tue, Jan 6, 2015 at 5:27 PM, Bryan Drewery wrote: > > On 1/6/2015 4:00 PM, Bryan Venteicher wrote: > > > On Tue, Jan 6, 2015 at 2:52 PM, John Nielsen > > > > > > wrote: > > > Bryan- > > > > > > On Oct 10, 2014, at 12:09 AM, Bryan Venteicher > > > > > > wrote: > > > > Author: bryanv > > > > Date: Fri Oct 10 06:08:59 2014 > > > > New Revision: 272886 > > > > URL: https://svnweb.freebsd.org/changeset/base/272886 > > > > > > > > Log: > > > > Add context pointer and source address to the UDP tunnel callback > > > > > > > > These are needed for the forthcoming vxlan implementation. The > > > > context > > > > > > pointer means we do not have to use a spare pointer field in the > > > > inpcb, > > > > > > and the source address is required to populate vxlan's forwarding > > > > table. > > > > > > While I highly doubt there is an out of tree consumer of the UDP > > > > tunneling callback, this change may be a difficult to eventually > > > > MFC. > > > > > I noticed this comment while doing an MFC of vxlan to my local tree. > > > Do you think an MFC to 10-STABLE of this change (and vxlan > > > generally) will be feasible? Is there precedent for ABI changes like > > > this being sanctioned? Could symbol versioning help? > > > > > > I'd like to get some consensus on whether this commit is OK to MFC. With > > > this commit, vxlan should be an easy to MFC. > > > > Breaking ABI will potentially hurt packages. FreeBSD builds packages for > > the oldest supported release on a branch. If you break ABI in 10.2 while > > we are building packages for 10.1 then any packages using these > > interfaces may not work right or result in panics packages with kmods. > > Please consider that. > > The only user visible change of this commit would be the addition of a > field at the end of 'struct udpcb'. I don't think that is a problem, at > least a similar change didn't prevent the MFC of UDP Lite. > > The kernel part of this changes the UDP tunneling functions which I guess > there could be a 3rd party module out there, but I very highly doubt that, > based on how un-useful the previous interface was. Userland should not be impacted by this at all. (Nothing in userland cares about udpcb's internals.) I think there was only ever one consumer for the existing UDP tunneling code (bz@ knows what it is). I'm not sure where it lives. -- John Baldwin