x86: simplify "make ARCH=x86" and fix kconfig all.config

Simplify "make ARCH=x86" and fix kconfig so we again can set 64BIT in all.config.

For a fix the diffstat is nice:

 6 files changed, 3 insertions(+), 36 deletions(-)

The patch reverts these commits:
0f855aa64b3f63d35a891510cf7db932a435c116
-> kconfig: add helper to set config symbol from environment variable

2a113281f5cd2febbab21a93c8943f8d3eece4d3
-> kconfig: use $K64BIT to set 64BIT with all*config targets

Roman Zippel pointed out that kconfig supported string compares so the additional complexity introduced by the above two patches were not needed.

With this patch we have following behaviour:

# make {allno,allyes,allmod,rand}config [ARCH=...]
option \ host arch      | 32bit         | 64bit
=====================================================
./.                     | 32bit         | 64bit
ARCH=x86                | 32bit         | 32bit
ARCH=i386               | 32bit         | 32bit
ARCH=x86_64             | 64bit         | 64bit

The general rule are that ARCH= and native architecture takes precedence over the configuration.
So make ARCH=i386 [whatever] will always build a 32-bit kernel no matter what the configuration says. The configuration will be updated to 32-bit if it was configured to 64-bit and the other way around.

This behaviour is consistent with previous behaviour so no suprises here.

make ARCH=x86 will per default result in a 32-bit kernel but as the only ARCH= value x86 allow the user to select between 32-bit and 64-bit using menuconfig.

---

Linus - please apply to -rc3.

Note: This patch does not fix the uname -m issue - to do so Andreas' patch is needed.

Sam

 Makefile                    |    4 +---
 README                      |    2 --
 arch/x86/Kconfig            |    4 ++--
 scripts/kconfig/conf.c      |    1 -
 scripts/kconfig/confdata.c  |   27 ---------------------------
 scripts/kconfig/lkc_proto.h |    1 -
 6 files changed, 3 insertions(+), 36 deletions(-)

index 9c9c4bf..b32963a 100644
@@ -200,11 +200,9 @@ SRCARCH 	:= $(ARCH)
 # Additional ARCH settings for x86
 ifeq ($(ARCH),i386)
         SRCARCH := x86
-        K64BIT  := n
 endif
 ifeq ($(ARCH),x86_64)
         SRCARCH := x86
-        K64BIT  := y
 endif
 
 KCONFIG_CONFIG	?= .config

@@ -341,7 +339,7 @@ KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
 KERNELVERSION = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)
 
 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
-export ARCH SRCARCH K64BIT CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
+export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
 export CPP AR NM STRIP OBJCOPY OBJDUMP MAKE AWK GENKSYMS PERL UTS_MACHINE
 export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
 

index 592f8a2..159912c 100644
@@ -194,8 +194,6 @@ CONFIGURING the kernel:
    "make *config" checks for a file named "all{yes/mod/no/random}.config"
    for symbol values that are to be forced.  If this file is not found,
    it checks for a file named "all.config" to contain forced values.
-   Finally it checks the environment variable K64BIT and if found, sets
-   the config symbol "64BIT" to the value of the K64BIT variable.
    
 	NOTES on "make config":
 	- having unnecessary drivers will make the kernel bigger, and can

index 1eb5997..368864d 100644
@@ -3,8 +3,8 @@ mainmenu "Linux Kernel Configuration for x86"
 
 # Select 32 or 64 bit
 config 64BIT
-	bool "64-bit kernel"
-	default n
+	bool "64-bit kernel" if ARCH = "x86"
+	default ARCH = "x86_64"
 	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

index c6bee85..a38787a 100644
@@ -591,7 +591,6 @@ int main(int ac, char **av)
 			conf_read_simple(name, S_DEF_USER);
 		else if (!stat("all.config", &tmpstat))
 			conf_read_simple("all.config", S_DEF_USER);
-		conf_set_env_sym("K64BIT", "64BIT", S_DEF_USER);
 		break;
 	default:
 		break;

index e4fa3f3..e0f402f 100644
@@ -145,33 +145,6 @@ static int conf_set_sym_val(struct symbol *sym, int def, int def_flags, char *p)
 	return 0;
 }
 
-/* Read an environment variable and assign the value to the symbol */
-int conf_set_env_sym(const char *env, const char *symname, int def)
-{
-	struct symbol *sym;
-	char *p;
-	int def_flags;
-
-	p = getenv(env);
-	if (p) {
-		char warning[200];
-		sprintf(warning, "Environment variable (%s = \"%s\")", env, p);
-		conf_filename = warning;
-		def_flags = SYMBOL_DEF << def;
-		if (def == S_DEF_USER) {
-			sym = sym_find(symname);
-			if (!sym)
-				return 1;
-		} else {
-			sym = sym_lookup(symname, 0);
-			if (sym->type == S_UNKNOWN)
-				sym->type = S_OTHER;
-		}
-		conf_set_sym_val(sym, def, def_flags, p);
-	}
-	return 0;
-}
-
 int conf_read_simple(const char *name, int def)
 {
 	FILE *in = NULL;

index dca294e..4d09f6d 100644
@@ -1,7 +1,6 @@
 
 /* confdata.c */
 P(conf_parse,void,(const char *name));
-P(conf_set_env_sym,int,(const char *envname, const char *symname, int def));
 P(conf_read,int,(const char *name));
 P(conf_read_simple,int,(const char *name, int));
 P(conf_write,int,(const char *name));

Linus,

The issue Sam refers to is that UTS_MACHINE is set to "x86" instead of "i386" or "x86_64" when building with ARCH=x86. Thus the new kernel when booted will give either "x86" on x86_64 and many i386 systems or even "x66" on other i386 systems for 'uname -m'.

Many tools rely on the usual values of "x86_64", "i366" and "i686" here. So we shouldn't change this.

Attached patch fixes that issue. Please apply.

Regards,

Andreas

--
x86: fix UTS_MACHINE to be i386 for 32-bit build and x86_64 for 64-bit build

---
 arch/x86/Makefile |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)

index 116b03a..7aa1dc6 100644
@@ -11,10 +11,9 @@ endif
 $(srctree)/arch/x86/Makefile%: ;
 
 ifeq ($(CONFIG_X86_32),y)
+        UTS_MACHINE := i386
         include $(srctree)/arch/x86/Makefile_32
 else
+        UTS_MACHINE := x86_64
         include $(srctree)/arch/x86/Makefile_64
 endif
-
-
-

1.5.3.4

Andreas - I will suggest you to submit a new patch with a better changelog where you jsut describe what you fix. The above explanations looks a bit weird if read stand alone.

You can always add additional comments after the line containing:
---

In this way it is not included in the changelog but Linus can read it.

Anyway - your patch has my ack.

Sam

Ok, I'll resend the patch with an updated changelog asap.

Thanks,

Andreas

Upon request I have updated the patch description
and hope it is now more explanatory.

IMHO this should go into 2.6.24.
BTW, the patch was tested with v2.6.24-rc3-19-g2ffbb83.

Regards,

Andreas

--
x86: correctly set UTS_MACHINE for "make ARCH=x86"

For a kernel built with "make ARCH=x86" the following system information is displayed when running the new kernel

    $ uname -m
    x86

On some i386 systems (e.g. K7) we even have the following information

    $ uname -m
    x66

This is weird. The usual information for "uname -m" should be "x86_64" on 64-bit and "i386" or "i686" on 32-bit.

This patch fixes the issue by setting UTS_MACHINE to "i386" for 32-bit kernel builds and to "x86_64" for 64-bit kernel builds. I.e., "x86" won't be used for UTS_MACHINE anymore.

---
 arch/x86/Makefile |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)

index 116b03a..7aa1dc6 100644
@@ -11,10 +11,9 @@ endif
 $(srctree)/arch/x86/Makefile%: ;
 
 ifeq ($(CONFIG_X86_32),y)
+        UTS_MACHINE := i386
         include $(srctree)/arch/x86/Makefile_32
 else
+        UTS_MACHINE := x86_64
         include $(srctree)/arch/x86/Makefile_64
 endif
-
-
-

1.5.3.4