Hi Masahiro,
On Wed, Aug 23, 2023 at 09:08:16PM +0900, Masahiro Yamada wrote:
> Revert the following two commits:
>
> - 7273ad2b08f8 ("kbuild: link lib-y objects to vmlinux forcibly when CONFIG_MODULES=y")
> - 7f2084fa55e6 ("[kbuild] handle exports in lib-y objects reliably")
>
> Now, lib-y is back to static library again, and the link order is
> consistent w/wo CONFIG_MODULES.
>
> Since commit ddb5cdbafaaa ("kbuild: generate KSYMTAB entries by
> modpost"), .vmlinux.export.c contains references to exported symbols.
> If a symbol in a lib-y object is exported, that object is always linked
> even without any explicit user in vmlinux.
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> ---
>
> Makefile | 5 -----
> 1 file changed, 5 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index 87a9eef3fb4b..71e9c65d9eae 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -1113,12 +1113,7 @@ export ARCH_DRIVERS := $(drivers-y) $(drivers-m)
> # Externally visible symbols (used by link-vmlinux.sh)
>
> KBUILD_VMLINUX_OBJS := ./built-in.a
> -ifdef CONFIG_MODULES
> -KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
> -KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
> -else
> KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
> -endif
>
> export KBUILD_VMLINUX_LIBS
> export KBUILD_LDS := arch/$(SRCARCH)/kernel/vmlinux.lds
> --
> 2.39.2
>
The build error that prompted 7273ad2b08f8 from [1] appears to return
with this patch, for example:
$ make -skj"$(nproc)" ARCH=arm64 LLVM=1 O=build mrproper virtconfig all
...
ERROR: modpost: "__memcat_p" [drivers/hwtracing/stm/stm_core.ko] undefined!
...
[1]: https://github.com/ClangBuiltLinux/linux/issues/515
Cheers,
Nathan
