On Sun, Aug 13, 2023 at 06:05:03PM +0800, Zhangjin Wu wrote:
I think that later I'll further extend XARCH with new variants to support ARMv5 and Thumb2, because we have different code for this and I continue to manually change the CFLAGS to test both.
Ok, what about further add x86_64 as the default variant for x86 (like ppc for powerpc)? and then it is able to only resereve the variables for x86_64. I have prepared a patch for this goal in our new tinyconfig patchset, it will further avoid adding the same nolibc-test-x86.config and nolibc-test-x86_64.config.
I'm confused, x86 already defaults to x86_64, it's just that it depends on the .config itself to figure whether to produce a 32- or 64-bit kernel. But for example it starts qemu in 64-bit mode. Am I missing anything ?
In kernel side, it is, but in our nolibc-test, we have added a copy of x86_64 for x86:
$ grep -E "_x86" tools/testing/selftests/nolibc/Makefile IMAGE_x86_64 = arch/x86/boot/bzImage IMAGE_x86 = arch/x86/boot/bzImage CROSS_COMPILE_x86_64 ?= x86_64-linux- x86_64-linux-gnu- CROSS_COMPILE_x86 ?= x86_64-linux- x86_64-linux-gnu- DEFCONFIG_x86_64 = defconfig DEFCONFIG_x86 = defconfig QEMU_ARCH_x86_64 = x86_64 QEMU_ARCH_x86 = x86_64 QEMU_ARGS_x86_64 = -M pc -append "console=ttyS0,9600 i8042.noaux panic=-1 $(TEST:%=NOLIBC_TEST=%)" QEMU_ARGS_x86 = -M pc -append "console=ttyS0,9600 i8042.noaux panic=-1 $(TEST:%=NOLIBC_TEST=%)"
With 'XARCH', the "_x86" copy of them can be simply replaced with such a line:
# configure default variants for target kernel supported architectures XARCH_powerpc = ppc +XARCH_x86 = x86_64 XARCH = $(or $(XARCH_$(ARCH)),$(ARCH))
And therefore, the future nolibc-test-x86_64.config is also enough for x86.
But I have seen the 'x86' exception in tools/include/nolibc/Makefile, just a confirm on if this replacement is ok.
BR, Zhangjin
Willy