From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 5389DAFF for ; Thu, 14 Aug 2014 08:50:09 +0000 (UTC) Received: from mail.active-venture.com (mail.active-venture.com [67.228.131.205]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id BDB321F8B2 for ; Thu, 14 Aug 2014 08:50:08 +0000 (UTC) Message-ID: <53EC7839.3010704@roeck-us.net> Date: Thu, 14 Aug 2014 01:50:01 -0700 From: Guenter Roeck MIME-Version: 1.0 To: Geert Uytterhoeven References: <20140813180743.GB16662@roeck-us.net> <20140813224507.GA29606@roeck-us.net> In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Cc: "ksummit-discuss@lists.linuxfoundation.org" Subject: Re: [Ksummit-discuss] RFC: Kernel tinification - kernel config reduction List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi Geert, On 08/14/2014 12:40 AM, Geert Uytterhoeven wrote: >>> >> Maybe something like >> >> make PCI=n allmodconfig >> make GPIOLIB=n allmodconfig >> >> which would let me disable key options selectively so I can improve compile >> coverage without having to go through all configurations (or randconfig). > > That's doable, using KCONFIG_ALLCONFIG. > I'll play with it some more, but a quick glance (and test) suggests that I can only use it to force a configuration option to be true, not to force it to be false. Also, there seems to be an odd side effect. With kconfig.gpio: "CONFIG_GPIOLIB=y" and kconfig.nogpio: "# CONFIG_GPIOLIB is not set" KCONFIG_ALLCONFIG=kconfig.gpio make allnoconfig causes CONFIG_GPIOLIB to be set. KCONFIG_ALLCONFIG=kconfig.gpio make allmodconfig KCONFIG_ALLCONFIG=kconfig.nogpio make allmodconfig both have the odd and at least for me unexpected effect of disabling CONFIG_MODULES, but do not affect CONFIG_GPIOLIB. >>> You also only build some of the allmodconfigs? >>> >> Never "only". I always also build defconfig, plus at least sometimes a couple >> of additional configurations (if available) to improve coverage of conditional >> functionality. > > Sorry, should have said "only some of the allmodconfigs". > I noticed for e.g. m68k you build defconfig and allmodconfig (and a nommu > config), but for some other architectures only defconfig. > I only use 'allmodconfig' and/or 'allyesconfig' if I can be reasonably sure that the architecture maintainers care about it. That goes back to 3.10ish when I started the -stable-queue builds; I only added allmodconfig/allyesconfig to the list of builds if it built when I added the architecture. I didn't check recently if I can add some more, so I may miss a couple of architectures which do now build. Guenter