From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754038AbZF3LKn (ORCPT ); Tue, 30 Jun 2009 07:10:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752647AbZF3LKi (ORCPT ); Tue, 30 Jun 2009 07:10:38 -0400 Received: from casper.infradead.org ([85.118.1.10]:34051 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752059AbZF3LKh (ORCPT ); Tue, 30 Jun 2009 07:10:37 -0400 Subject: Re: [PATCH] Don't override CONFIG_64BIT for ARCH={i386,x86_64} builds From: David Woodhouse To: Ingo Molnar Cc: x86 maintainers , linux-kernel@vger.kernel.org In-Reply-To: <20090212072644.GA10253@elte.hu> References: <1234372298.3586.23.camel@macbook.infradead.org> <20090211172258.GE13239@elte.hu> <20090212072644.GA10253@elte.hu> Content-Type: text/plain Date: Tue, 30 Jun 2009 12:10:21 +0100 Message-Id: <1246360221.3681.96.camel@macbook.infradead.org> Mime-Version: 1.0 X-Mailer: Evolution 2.26.2 (2.26.2-1.fc11) Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2009-02-12 at 08:26 +0100, Ingo Molnar wrote: > > i removed it again, because it regresses randconfig behavior: > > titan:~/tip> grep X86_32 .config; make ARCH=x86_64 randconfig; grep > X86_32 .config > # CONFIG_X86_32 is not set > scripts/kconfig/conf -r arch/x86/Kconfig > # > # configuration written to .config > # > CONFIG_X86_32=y > CONFIG_X86_32_SMP=y > CONFIG_X86_32_LAZY_GS=y > CONFIG_X86_32_ALWAYS_ON=y > > I dont mind the change you are after, but randconfig should work as > expected too: if ARCH=x86_64 is passed it should generate a 64-bit > randconfig, not a 50% 32-bit one. I still think that's a crap argument -- randconfig is _supposed_ to give you a random config -- it's not as if you're going to boot it anyway. If you want to have a _partially_ random config you should do that with something like 'make CONFIG_FOO=y randconfig'. I think we should drop the historical baggage of 'ARCH=i386' and 'ARCH=x86_64' completely. But I've just spent a few days testing the wrong damn kernel because 'make oldconfig' silently changed architectures on the config I was given to test -- a bug which you seem to think is _less_ important than the 'bug' that randconfig actually gives you what you asked for. So I'll have another go at fixing it in a way that preserves your silly 'make ARCH=x86_64 almost-random-config', this time by letting $(ARCH) default to x86. I didn't do it this way before, because I wanted 'make defconfig' to give you a config which matched the architecture you're running on. I've achieved that a different way now though. For those using 'make config' from scratch, I made it default to x86_64 instead of i386. That's probably a saner choice, these days. -------------- Subject: Don't silently override CONFIG_64BIT in 'make oldconfig' It is a steaming great pain in the arse when the value of CONFIG_64BIT explicitly written in my .config file is overridden by the value of $ARCH inferred from the environment. If I have a 32-bit .config and I happen to build it without remembering to put 'ARCH=i386' on the make command line, it shouldn't force CONFIG_64BIT=y and reconfigure. This patch should fix that, while still allowing defconfig to work as it currently does for both 32-bit and 64-bit environments. The default when running 'make config' is no longer automatic -- it's set to 64-bit. It wasn't possible to preserve this behaviour without also breaking things for the strange people who want 'make randconfig' not to actually be completely random. Signed-off-by: David Woodhouse diff --git a/Makefile b/Makefile index d1216fe..c944d6e 100644 --- a/Makefile +++ b/Makefile @@ -157,7 +157,8 @@ export srctree objtree VPATH TOPDIR # then ARCH is assigned, getting whatever value it gets normally, and # SUBARCH is subsequently ignored. -SUBARCH := $(shell uname -m | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \ +SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \ + -e s/sun4u/sparc64/ \ -e s/arm.*/arm/ -e s/sa110/arm/ \ -e s/s390x/s390/ -e s/parisc64/parisc/ \ -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \ diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index d1430ef..3f5bbfe 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -4,7 +4,7 @@ mainmenu "Linux Kernel Configuration for x86" # Select 32 or 64 bit config 64BIT bool "64-bit kernel" if ARCH = "x86" - default ARCH = "x86_64" + default ARCH != "i386" ---help--- Say yes to build a 64-bit kernel - formerly known as x86_64 Say no to build a 32-bit kernel - formerly known as i386 diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 1b68659..3c6c6ea 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -2,7 +2,11 @@ # select defconfig based on actual architecture ifeq ($(ARCH),x86) + ifeq ($(shell uname -m),x86_64) + KBUILD_DEFCONFIG := x86_64_defconfig + else KBUILD_DEFCONFIG := i386_defconfig + endif else KBUILD_DEFCONFIG := $(ARCH)_defconfig endif -- David Woodhouse Open Source Technology Centre David.Woodhouse@intel.com Intel Corporation