Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261509AbVDCGCM (ORCPT ); Sun, 3 Apr 2005 01:02:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261522AbVDCGCM (ORCPT ); Sun, 3 Apr 2005 01:02:12 -0500 Received: from e6.ny.us.ibm.com ([32.97.182.146]:32977 "EHLO e6.ny.us.ibm.com") by vger.kernel.org with ESMTP id S261509AbVDCGBt (ORCPT ); Sun, 3 Apr 2005 01:01:49 -0500 Date: Sat, 2 Apr 2005 22:02:00 -0800 From: "Paul E. McKenney" To: Adrian Bunk Cc: Andrew Morton , Dipankar Sarma , Manfred Spraul , linux-kernel@vger.kernel.org Subject: Re: [2.6 patch] kernel/rcupdate.c: make the exports EXPORT_SYMBOL_GPL Message-ID: <20050403060200.GA1332@us.ibm.com> Reply-To: paulmck@us.ibm.com References: <20050327143454.GJ4285@stusta.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050327143454.GJ4285@stusta.de> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2982 Lines: 64 On Sun, Mar 27, 2005 at 04:34:54PM +0200, Adrian Bunk wrote: > Due to the patent situation at least in the USA, the exports of > kernel/rcupdate.c should be EXPORT_SYMBOL_GPL. Based on -what- line of reasoning??? The obvious ones do not apply to this situation. These need to be put back. Moving them to GPL -- but in a measured manner, as I proposed on this list some months ago -- is fine. Changing these particular exports precipitously is most definitely -not- fine. Here is my earlier proposal: http://marc.theaimsgroup.com/?l=linux-kernel&m=110520930301813&w=2 See below for a patch that puts the exports back, along with an updated version of my earlier patch that starts the process of moving them to GPL. I will also be following this message with RFC patches that introduce two (EXPORT_SYMBOL_GPL) interfaces to replace synchronize_kernel(), which then becomes deprecated. Andrew, please apply. Thanx, Paul Signed-off-by: diff -urpN -X ../dontdiff linux-2.5-notyet/kernel/rcupdate.c linux-2.5/kernel/rcupdate.c --- linux-2.5-notyet/kernel/rcupdate.c Sat Apr 2 17:15:14 2005 +++ linux-2.5/kernel/rcupdate.c Sat Apr 2 07:54:30 2005 @@ -465,6 +465,6 @@ void synchronize_kernel(void) } module_param(maxbatch, int, 0); -EXPORT_SYMBOL_GPL(call_rcu); -EXPORT_SYMBOL_GPL(call_rcu_bh); -EXPORT_SYMBOL_GPL(synchronize_kernel); +EXPORT_SYMBOL(call_rcu); /* WARNING: GPL-only in April 2006. */ +EXPORT_SYMBOL(call_rcu_bh); /* WARNING: GPL-only in April 2006. */ +EXPORT_SYMBOL(synchronize_kernel); /* WARNING: GPL-only in April 2006. */ diff -urpN -X ../dontdiff linux-2.5-2005.04.02/Documentation/feature-removal-schedule.txt linux-2.5-2005.04.02-01/Documentation/feature-removal-schedule.txt --- linux-2.5-2005.04.02/Documentation/feature-removal-schedule.txt Sat Apr 2 07:48:46 2005 +++ linux-2.5-2005.04.02-01/Documentation/feature-removal-schedule.txt Sat Apr 2 21:16:24 2005 @@ -15,3 +15,16 @@ Why: It has been unmaintained for a numb against the LSB, and can be replaced by using udev. Who: Greg Kroah-Hartman +What: RCU API moves to EXPORT_SYMBOL_GPL +When: April 2006 +Files: include/linux/rcupdate.h, kernel/rcupdate.c +Why: Outside of Linux, the only implementations of anything even + vaguely resembling RCU that I am aware of are in DYNIX/ptx, + VM/XA, Tornado, and K42. I do not expect anyone to port binary + drivers or kernel modules from any of these, since the first two + are owned by IBM and the last two are open-source research OSes. + So these will move to GPL after a grace period to allow + people, who might be using implementations that I am not aware + of, to adjust to this upcoming change. +Who: Paul E. McKenney + - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/