On 18-Feb-2025 03:26:39 PM, Kienan Stewart wrote:
> In the upstream commit 214c0eea43b2ea66bcd6467ea57e47ce8874191b
> ("kbuild: add $(objtree)/ prefix to some in-kernel build artifacts")
> artifacts required for building out-of-tree kernel modules had
> $(objtree) prepended to them to prepare for building in other
> directories.
>
> When building external modules for powerpc,
> arch/powerpc/lib/crtsavres.o is required for certain
> configurations. This artifact is missing the prepended $(objtree).
FYI, the issue resolved here breaks the build of LTTng-modules against
recent kernels on powerpc. I would gladly welcome upstreaming of this
fix into the Linux kernel.
Thanks!
Mathieu
>
> Fixes: 13b25489b6f8 ("kbuild: change working directory to external module
> directory with M=")
> Acked-by: Masahiro Yamada <masahi...@kernel.org>
> Reviewed-by: Nicolas Schier <n.sch...@avm.de>
> Tested-by: Nicolas Schier <n.sch...@avm.de>
> Signed-off-by: Kienan Stewart <kstew...@efficios.com>
> ---
> Changes in v2:
> - Added Review-by/Tested-by/Fixes/Acked-By
> - Removed mention of possible work-around for external modules (while
> the build will pass, `make modules_install` will fail)
> - Link to v1:
> https://lore.kernel.org/r/20250127-buildfix-extmod-powerpc-v1-1-450012b16...@efficios.com
> ---
> arch/powerpc/Makefile | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
> index
> f3804103c56ccfdb16289468397ccaea71bf721e..9933b98df69d7f7b9aaf33d36155cc61ab4460c7
> 100644
> --- a/arch/powerpc/Makefile
> +++ b/arch/powerpc/Makefile
> @@ -58,7 +58,7 @@ ifeq ($(CONFIG_PPC64)$(CONFIG_LD_IS_BFD),yy)
> # There is a corresponding test in arch/powerpc/lib/Makefile
> KBUILD_LDFLAGS_MODULE += --save-restore-funcs
> else
> -KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
> +KBUILD_LDFLAGS_MODULE += $(objtree)/arch/powerpc/lib/crtsavres.o
> endif
>
> ifdef CONFIG_CPU_LITTLE_ENDIAN
>
> ---
> base-commit: ffd294d346d185b70e28b1a28abe367bbfe53c04
> change-id: 20250127-buildfix-extmod-powerpc-a744e1331f83
>
> Best regards,
> --
> Kienan Stewart <kstew...@efficios.com>
>
--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com
