From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from forward3l.mail.yandex.net ([84.201.143.136]:55727 "EHLO forward3l.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753114AbaINRcL (ORCPT ); Sun, 14 Sep 2014 13:32:11 -0400 Message-ID: <5415D10E.90809@yandex.ru> Date: Sun, 14 Sep 2014 21:31:58 +0400 From: Kirill Tkhai Reply-To: tkhai@yandex.ru MIME-Version: 1.0 Subject: Re: [PATCH 0/3] Implement /proc/built-in file similar to /proc/modules References: <20140914100545.3745.23394.stgit@localhost> <20140914153832.GC4064@kroah.com> In-Reply-To: <20140914153832.GC4064@kroah.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: Greg KH Cc: mmarek@suse.cz, arnd@arndb.de, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, oleg@redhat.com, grant.likely@secretlab.ca, ebiederm@xmission.com, akpm@linux-foundation.org, ktkhai@parallels.com, sam@ravnborg.org On 14.09.2014 19:38, 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? There are only the drivers in "/sys/module" which have parameters. Drivers without parameters do not appear there. >> So, if your system has "loop" driver then it appears either in /proc/modules >> or in /proc/built-in and userspace will be able to know about this. >> >> Now this is impossible. The only way to get kernel configuration is >> /proc/config.gz, but CONFIG_* names can change from time to time. Module >> names are more or less standardized. > > Module names aren't "standardized", we change them at times when needed, > just like CONFIG_ names. > > 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. It looks like userspace applications oriented on modules names rather than on CONFIG_XXX parameters. /proc/config.gz is optional and userspace applications can't base on it. For example, when I compile "loop" module built-in and "loop" is in /etc/modules, init script warns about this module is not present and can't be autoloaded. The script does not store CONFIG_XXX <-> module_xxx conformity. And nobody stores it. When iptables wants extra functionality, it requests a module. Etc. Nobody is oriented on CONFIG_XXX parameters. It would be simple for userspace to add a support of /proc/built-in analysing. It's very similar to /proc/modules.