Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754267Ab3GPJZU (ORCPT ); Tue, 16 Jul 2013 05:25:20 -0400 Received: from p-mail2.rd.orange.com ([195.101.245.16]:26310 "EHLO p-mail2.rd.orange.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752815Ab3GPJZS (ORCPT ); Tue, 16 Jul 2013 05:25:18 -0400 From: "Yann E. MORIN" To: Florian Fainelli Subject: Re: [PATCH -next 2/2] kbuild: fix for updated LZ4 tool with the new streaming format Date: Tue, 16 Jul 2013 11:25:14 +0200 User-Agent: KMail/1.13.5 (Linux/3.9.10-ilmarinen-nv; KDE/4.4.5; x86_64; ; ) Cc: Andrew Morton , "H. Peter Anvin" , Ingo Molnar , Kyungsik Lee , Michal Marek , "linux-kernel@vger.kernel.org" , linux-kbuild@vger.kernel.org, x86@kernel.org, celinux-dev@lists.celinuxforum.org, "linux-arm-kernel@lists.infradead.org" , hyojun.im@lge.com, chan.jeong@lge.com, Andy Lee , Ingo Molnar , Thomas Gleixner , Russell King , Borislav Petkov , Yann Collet , Chanho Min References: <1367829775-4434-1-git-send-email-kyungsik.lee@lge.com> <20130716005611.e4ccab02.akpm@linux-foundation.org> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201307161125.14491.yann.morin.1998@free.fr> X-OriginalArrivalTime: 16 Jul 2013 09:25:14.0837 (UTC) FILETIME=[60F47050:01CE8206] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2786 Lines: 73 Florian, All, On Tuesday 16 July 2013 11:13:24 Florian Fainelli wrote: > 2013/7/16 Andrew Morton : > > On Tue, 16 Jul 2013 00:47:27 -0700 Andrew Morton wrote: > > > >> On Mon, 15 Jul 2013 15:08:20 -0700 "H. Peter Anvin" wrote: > >> > >> > On 07/15/2013 03:03 PM, Andrew Morton wrote: > >> > > > >> > > I don't know how to do this. Any suggestions? > >> > > > >> > > It has to be done at `make config' time. We'd need to probe for the > >> > > presence of lz4c and then.... what? > >> > > > >> > > Is there any precedent for this? > >> > > > >> > > I don't think we can just ignore the absence of lz4c - the user has > >> > > selected a config which his system cannot build. The problem lies > >> > > within randconfig itself. > >> > > > >> > > >> > We keep running over the need to be able to have kconfig run tests on > >> > the build system (for toolchain support or for optional tools needed); > >> > running them in the Makefiles (i.e. at Kbuild time) is simply too late. > >> > > >> > >> Would it make sense to extend Kconfig's `depends'? > >> > >> depends on $(shell-command) > >> > >> I don't know how practical that would be to implement... > > > > Or, easier and faster, run some front-end script which generates > > once-off Kconfig symbols. > > > > if [ -x /bin/lz4c ] > > then > > echo CONFIG_HAVE_LZ4C > > fi > > > > then munge the output of that script into the Kconfig run and do > > > > depends on HAVE_LZ4C > > That does sound nice to avoid the build error, but will eventually > make it harder to diagnose why the kernel has not been compressed with > the specific compression tool, some kind of warning should also be > emitted maybe? Either a warning at check-time, or a comment in Kconfig, such as: config COMPRESS_LZ4 depends on HAVE_LZ4 comment "'lz4' missing, LZ4 compression not available" depends on !HAVE_LZ4 Either way is fine with me. ;-) Regards, Yann E. MORIN. -- .-----------------.--------------------.------------------.--------------------. | Yann E. MORIN | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: | | +0/33 662376056 | Software Designer | \ / CAMPAIGN | ^ | | --==< O_o >==-- '------------.-------: X AGAINST | /e\ There is no | | http://ymorin.is-a-geek.org/ | (*_*) | / \ HTML MAIL | """ conspiracy. | '------------------------------'-------'------------------'--------------------' -- 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/