From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752890AbaINRaG (ORCPT ); Sun, 14 Sep 2014 13:30:06 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40705 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752863AbaINRaD (ORCPT ); Sun, 14 Sep 2014 13:30:03 -0400 Date: Sun, 14 Sep 2014 19:27:09 +0200 From: Oleg Nesterov To: Greg KH Cc: Kirill Tkhai , mmarek@suse.cz, arnd@arndb.de, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, grant.likely@secretlab.ca, ebiederm@xmission.com, akpm@linux-foundation.org, ktkhai@parallels.com, sam@ravnborg.org Subject: Re: [PATCH 0/3] Implement /proc/built-in file similar to /proc/modules Message-ID: <20140914172709.GA1569@redhat.com> References: <20140914100545.3745.23394.stgit@localhost> <20140914153832.GC4064@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140914153832.GC4064@kroah.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/14, Greg KH wrote: > > On Sun, Sep 14, 2014 at 02:18:13PM +0400, Kirill Tkhai wrote: > > This series implements a possibility to show the list of built-in drivers > > to userspace. The names of drivers will be the same as when they are modules. > > Have you looked at /sys/modules/ ? Doesn't that show what you want > here? Well, /sys/module/ doesn't list the modules (drivers) compiled in. Say, /sys/module/kernel. And it can't help a user to figure out that, say, the loop driver is already "loaded" because CONFIG_BLK_DEV_LOOP=y. > Module names aren't "standardized", we change them at times when needed, > just like CONFIG_ names. OK, but still the name will be the same, in /proc/modules or /proc/builtin. > What is your end goal here? As you say, config.gz is the real kernel > configuration, just having a list of modules built in isn't going to > help much in getting a working kernel config without it. Perhaps you are right... but otoh perhaps this can can be useful anyway. Again, a user can know about "insmod loop", but he can know nothing about CONFIG_ names. That said, I do not really understand 2/3. Not only I do not understand this kbuild magic, I am not sure I understand what /proc/built-in will actually show. To me it would be better to change the "ifndef MODULE" version of module_init() to add KBUILD_MODNAME into __builtin_drivers_list[]. Yes, module_init() is overused. Say, why does kernel/kprobes.c use module_init() ? This looks confusing, this code can't be compiled as a module. And it seems that it has a lot more users which should have used __initcall() instead. In short, I dunno ;) Oleg.