Fwd: [PATCH v4 07/17] kbuild: generate module BTF based on vmlinux.unstripped

[Thomas Weißschuh]

Hi BPF/BTF maintainers,

could you take a look at the patch quoted below?
It is part of a patch series which only tangentially touches BTF [0].
If you prefer to receive the full patch series, please let me know and
I'll do that for the next revision.

[0] https://lore.kernel.org/lkml/20260113-module-hashes-v4-6-0b932db9b56b@xxxxxxxxxxxxxx/

Thomas

On 2026-01-13 13:28:51+0100, Thomas Weißschuh wrote:
> The upcoming module hashes functionality will build the modules in
> between the generation of the BTF data and the final link of vmlinux.
> At this point vmlinux is not yet built and therefore can't be used for
> module BTF generation. vmlinux.unstripped however is usable and
> sufficient for BTF generation.
> 
> Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
> ---
>  scripts/Makefile.modfinal | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal
> index adfef1e002a9..930db0524a0a 100644
> --- a/scripts/Makefile.modfinal
> +++ b/scripts/Makefile.modfinal
> @@ -40,11 +40,11 @@ quiet_cmd_ld_ko_o = LD [M]  $@
>  
>  quiet_cmd_btf_ko = BTF [M] $@
>        cmd_btf_ko = 							\
> -	if [ ! -f $(objtree)/vmlinux ]; then				\
> -		printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \
> +	if [ ! -f $(objtree)/vmlinux.unstripped ]; then			\
> +		printf "Skipping BTF generation for %s due to unavailability of vmlinux.unstripped\n" $@ 1>&2; \
>  	else								\
> -		LLVM_OBJCOPY="$(OBJCOPY)" $(PAHOLE) -J $(PAHOLE_FLAGS) $(MODULE_PAHOLE_FLAGS) --btf_base $(objtree)/vmlinux $@; \
> -		$(RESOLVE_BTFIDS) -b $(objtree)/vmlinux $@;		\
> +		LLVM_OBJCOPY="$(OBJCOPY)" $(PAHOLE) -J $(PAHOLE_FLAGS) $(MODULE_PAHOLE_FLAGS) --btf_base $(objtree)/vmlinux.unstripped $@; \
> +		$(RESOLVE_BTFIDS) -b $(objtree)/vmlinux.unstripped $@;	\
>  	fi;
>  
>  # Same as newer-prereqs, but allows to exclude specified extra dependencies
> 
> -- 
> 2.52.0
>