Re: [PATCH] powerpc: add crtsavres.o to always-y instead of extra-y

Jan Stancek
2024-01-30T10:00:20Z

On Tue, Nov 21, 2023 at 10:51:34AM +1000, Nicholas Piggin wrote:
>On Tue Nov 21, 2023 at 9:23 AM AEST, Masahiro Yamada wrote:
>> crtsavres.o is linked to modules. However, as explained in commit
>> d0e628cd817f ("kbuild: doc: clarify the difference between extra-y
>> and always-y"), 'make modules' does not build extra-y.
>>
>> For example, the following command fails:
>>
>> $ make ARCH=powerpc LLVM=1 KBUILD_MODPOST_WARN=1 mrproper ps3_defconfig modules
>> [snip]
>> LD [M] arch/powerpc/platforms/cell/spufs/spufs.ko
>> ld.lld: error: cannot open arch/powerpc/lib/crtsavres.o: No such file or directory
>> make[3]: *** [scripts/Makefile.modfinal:56: arch/powerpc/platforms/cell/spufs/spufs.ko] Error 1
>> make[2]: *** [Makefile:1844: modules] Error 2
>> make[1]: *** [/home/masahiro/workspace/linux-kbuild/Makefile:350: __build_one_by_one] Error 2
>> make: *** [Makefile:234: __sub-make] Error 2
>>
>
>Thanks. Is this the correct Fixes tag?
>
>Fixes: d0e628cd817f ("powerpc/64: Do not link crtsavres.o in vmlinux")
>
>Hmm, looks like LLD might just do this now automatically for us
>too without --save-restore-funcs (https://reviews.llvm.org/D79977).
>But we probably still need it for older versions, so we still need
>your patch.

Hi,

I'm still seeing the error of crtsavres.o missing when building external modules
after "make LLVM=1 modules_prepare". Should it be built also in archprepare?

Thanks,
Jan

diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 051247027..a62334194 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -57,8 +57,11 @@ ifeq ($(CONFIG_PPC64)$(CONFIG_LD_IS_BFD),yy)
# Have the linker provide sfpr if possible.
# There is a corresponding test in arch/powerpc/lib/Makefile
KBUILD_LDFLAGS_MODULE += --save-restore-funcs
+crtsavres_prepare:
else
KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
+crtsavres_prepare:
+ $(MAKE) $(build)=arch/powerpc/lib arch/powerpc/lib/crtsavres.o
endif

ifdef CONFIG_CPU_LITTLE_ENDIAN
@@ -389,7 +392,7 @@ vdso_prepare: prepare0
$(build)=arch/powerpc/kernel/vdso include/generated/vdso64-offsets.h)
endif

-archprepare: checkbin
+archprepare: checkbin crtsavres_prepare

archheaders:
$(Q)$(MAKE) $(build)=arch/powerpc/kernel/syscalls all