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 2AD8346 for ; Fri, 15 Aug 2014 11:05:01 +0000 (UTC) Received: from mail.active-venture.com (mail.active-venture.com [67.228.131.205]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id 0B9711F88A for ; Fri, 15 Aug 2014 11:05:00 +0000 (UTC) Message-ID: <53EDE958.1040200@roeck-us.net> Date: Fri, 15 Aug 2014 04:04:56 -0700 From: Guenter Roeck MIME-Version: 1.0 To: Geert Uytterhoeven References: <20140813180743.GB16662@roeck-us.net> <20140813224507.GA29606@roeck-us.net> <53EC7839.3010704@roeck-us.net> In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Cc: "ksummit-discuss@lists.linuxfoundation.org" , linux-kbuild Subject: Re: [Ksummit-discuss] RFC: Kernel tinification - kernel config reduction List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 08/14/2014 02:02 AM, Geert Uytterhoeven wrote: > Hi Günther, > > CC kbuild > > On Thu, Aug 14, 2014 at 10:50 AM, Guenter Roeck wrote: >> 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. > > Strange... > > I also saw strange things with randconfig, needing config input during the > subsequent build, or "make oldconfig" asking new questions, just after > having done a randconfig. > I made some progress. The following KCONFIG_ALLCONFIG file lets me disable GPIOLIB with x86_64, and still build everything as modules. # CONFIG_FB_VIA is not set # CONFIG_MFD_AAT2870_CORE is not set # CONFIG_MFD_ASIC3 is not set # CONFIG_GPIOLIB is not set CONFIG_MODULES=y I had to deselect everything which explicitly selects GPIOLIB. Kind of makes sense. For some reason it is necessary to specify "CONFIG_MODULES=y" even with "allmodconfig" when using a KCONFIG_ALLCONFIG file. Guenter