From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757834AbXFUSB3 (ORCPT ); Thu, 21 Jun 2007 14:01:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759041AbXFUSAb (ORCPT ); Thu, 21 Jun 2007 14:00:31 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:40035 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758525AbXFUSAa (ORCPT ); Thu, 21 Jun 2007 14:00:30 -0400 Date: Thu, 21 Jun 2007 19:00:29 +0100 From: Al Viro To: Alexandre Oliva Cc: linux-kernel@vger.kernel.org Subject: Re: how about mutual compatibility between Linux's GPLv2 and GPLv3? Message-ID: <20070621180029.GR21478@ftp.linux.org.uk> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 21, 2007 at 06:39:07AM -0300, Alexandre Oliva wrote: > Here's an idea that just occurred to me, after all the discussions > about motivations, tit-for-tat, authors' wishes and all. > > If GPLv3 were to have a clause that permitted combination/linking with > code under GPLv2, this wouldn't be enough for GPLv3 projects to use > Linux code, and it wouldn't be enough for Linux code to use GPLv3 > projects. That's because GPLv2 would still demand all code to be > licensed under GPLv2, and GPLv3 wouldn't permit this. > > However, if GPLv3 had a permission to combine/link with code under > GPLv2, *and* Linux (and any other projects interested in mutual > compatibility) introduced an additional permission to combine/link > with code under GPLv3 (or even GPLv3+, constrained by some condition > if you will), then: > > - the kernel Linux could use code from GPLv3 projects ... and inherit GPLv3 additional restrictions. No. > - GPLv3 projects could use code from Linux Oh, rapture! How could one object against such a glorious outcome? > - each copyright holder would still get to enforce the terms s/he > chose for his/her own code ... except for that pesky "no added restrictions" part, but hey, who cares? > If you were to permit compatibility with GPLv3+ (rather than GPLv3), > would you constrain it? Would something like: > > as long as the later version grants each licensee the same > permissions as GPLv2, except for constraining permissions that would > enable one licensee to deny other licensees the exercise of the > permissions granted by both licenses ... because it's For The Benefit Of User Freedoms!!! No. Permission denied. And I don't know of any suckers who would buy that and hadn't been already hooked by FSF peddlers already. If somebody wants to dual-license their code, they can do it just fine. If somebody wants to dual-license *others* code, they can go and play with themselves until they reach RMS-level clarity of vision.