From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964890AbVLFAxp (ORCPT ); Mon, 5 Dec 2005 19:53:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964891AbVLFAxo (ORCPT ); Mon, 5 Dec 2005 19:53:44 -0500 Received: from ppp-217-133-42-200.cust-adsl.tiscali.it ([217.133.42.200]:41557 "EHLO opteron.random") by vger.kernel.org with ESMTP id S964890AbVLFAxo (ORCPT ); Mon, 5 Dec 2005 19:53:44 -0500 Date: Tue, 6 Dec 2005 01:53:41 +0100 From: Andrea Arcangeli To: Tim Bird Cc: David Woodhouse , arjan@infradead.org, andrew@walrond.org, linux-kernel@vger.kernel.org Subject: Re: Linux in a binary world... a doomsday scenario Message-ID: <20051206005341.GN28539@opteron.random> References: <1133779953.9356.9.camel@laptopd505.fenrus.org> <200512051826.06703.andrew@walrond.org> <1133817575.11280.18.camel@localhost.localdomain> <1133817888.9356.78.camel@laptopd505.fenrus.org> <1133819684.11280.38.camel@localhost.localdomain> <4394D396.1020102@am.sony.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4394D396.1020102@am.sony.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 05, 2005 at 03:56:06PM -0800, Tim Bird wrote: > If the GPL covers interface linkages (whether static or > dynamic) then EXPORT_SYMBOL_GPL is redundant. If it does > not, in all cases, then EXPORT_SYMBOL_GPL is, as > an extension to GPL, therefore a GPL violation. The last time I spoke with Linus about this, what I understood can be described in two points: 1) EXPORT_SYMBOL_GPL is an hint: if you have to circumvent it, there are high chances that you're creating a derivative of the linux kernel and in turn there are high chances that you're illegal 2) The fact you're illegal or not, has nothing to do with the _GPL tag in the exports, the illegal usage is when the module create a derivative of the linux kernel. Now I don't know for sure myself (I'm not a lawyer) what is a derivative of the linux kernel (don't ask me), but the two above points are quite clear to me. I always thought the _GPL tag could have no direct legal implications and Linus confirmed it. The kernel is GPL so everyone can modify the exports or re-export symbols as usual, the exports are GPL code too. The guy who re-exports or remove a _GPL tag is just modifying a GPL code, so he's ok. The _GPL tag is useful as an hint to binary only vendors as as such it makes perfect sense.