Hi, On Fri, Jul 29, 2011 at 8:49 PM, David Woodhouse <dwmw2@xxxxxxxxxxxxx> wrote: > I *frequently* waste a bunch of time when I take a 32-bit .config from a > test machine and try to build it on a faster 64-bit system, and its > existing setting of CONFIG_64BIT=n gets *changed* to match the build host. > > This is because the default setting for $ARCH when discovered from > 'uname' is one of the legacy pre-x86-merge values (i386 or x86_64), > which effectively force the setting of CONFIG_64BIT to match. We should > default to ARCH=x86 instead, finally completing the merge that we > started so long ago. > > This patch preserves the behaviour of the legacy ARCH settings for commands > such as: > > make ARCH=x86_64 randconfig > make ARCH=i386 randconfig > > ... although since my commit "Enable 'make CONFIG_FOO=y oldconfig'" those > would be better expressed as: > > make CONFIG_64BIT=y randconfig > make CONFIG_64BIT=n randconfig > > ... since that is a more generic way to set *any* config option, and > there's no other technical reason to keep the legacy ARCH values around > any more just to achieve that purpose; they could be removed at any > time. > > Signed-off-by: David Woodhouse <David.Woodhouse@xxxxxxxxx> > Link: http://lkml.kernel.org/r/1306707270.2029.377.camel@xxxxxxxxxxxxxxxx > --- > v2: Explicitly turn off CONFIG_64BIT in i386_defconfig. The default for > CONFIG_64BIT has *changed* (from n to y) for ARCH=x86, so it needs to > be explicitly turned off or 'make i386_defconfig' will give you 64-bit. > v3: Same patch as before; just updated changelog. > > Makefile | 3 ++- > arch/x86/Kconfig | 2 +- > arch/x86/Makefile | 4 ++++ > arch/x86/configs/i386_defconfig | 1 + > 4 files changed, 8 insertions(+), 2 deletions(-) > > diff --git a/Makefile b/Makefile > index d018956..303df9b 100644 > --- a/Makefile > +++ b/Makefile > @@ -165,7 +165,8 @@ export srctree objtree VPATH > # 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 := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \ > + -e s/sun4u/sparc64/ \ > -e s/arm.*/arm/ -e s/sa110/arm/ \ > -e s/s390x/s390/ -e s/parisc64/parisc/ \ > -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \ > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index 153aa6f..9467fdd 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -1,7 +1,7 @@ > # Select 32 or 64 bit > config 64BIT > bool "64-bit kernel" if ARCH = "x86" > - default ARCH = "x86_64" > + default ARCH != "i386" If I'm reading this correctly, does this mean that someone doing an 'allyesconfig' on an i386 machine will get a configuration for a 64bits kernel[0] ? With your logic, you would require the user to manually specify CONFIG_64BIT=n, which should be automatic on such a system... This logic seems broken to me. - Arnaud [0]: both ARCH and SUBARCH will be x86, so the conditional will translate to 'y' > ---help--- > Say yes to build a 64-bit kernel - formerly known as x86_64 > Say no to build a 32-bit kernel - formerly known as i386 > diff --git a/arch/x86/Makefile b/arch/x86/Makefile > index b02e509..94c2d8c 100644 > --- a/arch/x86/Makefile > +++ b/arch/x86/Makefile > @@ -2,7 +2,11 @@ > > # select defconfig based on actual architecture > ifeq ($(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 > diff --git a/arch/x86/configs/i386_defconfig b/arch/x86/configs/i386_defconfig > index 2bf18059f..5f96c1c 100644 > --- a/arch/x86/configs/i386_defconfig > +++ b/arch/x86/configs/i386_defconfig > @@ -1,3 +1,4 @@ > +# CONFIG_64BIT is not set > CONFIG_EXPERIMENTAL=y > # CONFIG_LOCALVERSION_AUTO is not set > CONFIG_SYSVIPC=y > -- > 1.7.6 > > > > -- > dwmw2 > > -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
