Re: [PATCH v3 01/20] kbuild: do not allocate .modinfo in vmlinux

[Kees Cook <kees@kernel.org>]

On Thu, Sep 17, 2026 at 05:06:11PM +0100, Lorenzo Stoakes (ARM) wrote:
> -# .modinfo in vmlinux.unstripped is aligned to 8 bytes for compatibility with
> -# tools that expect vmlinux to have sufficiently aligned sections but the
> -# additional bytes used for padding .modinfo to satisfy this requirement break
> -# certain versions of kmod with
> -#
> -#   depmod: ERROR: kmod_builtin_iter_next: unexpected string without modname prefix
> -#
> -# Strip the trailing padding bytes after extracting .modinfo to comply with
> -# what kmod expects to parse.

This comment still seems useful here (afaict the stripping is still
happening with the "sed"). Maybe better to leave it, or future readers
are left wondering what the sed is for?

>  quiet_cmd_modules_builtin_modinfo = GEN     $@
> -      cmd_modules_builtin_modinfo = $(cmd_objcopy); \
> -                                    sed -i 's/\x00\+$$/\x00/g' $@; \
> -                                    chmod -x $@
> -
> -OBJCOPYFLAGS_modules.builtin.modinfo := -j .modinfo -O binary
> +      cmd_modules_builtin_modinfo = $(OBJCOPY) -O binary -j .modinfo --dump-section .modinfo=$@ $< $@.tmp; \
> +                                    rm -f $@.tmp; \
> +                                    sed -i 's/\x00\+$$/\x00/g' $@

Otherwise, looks good. With the comment back (or rewritten):

Reviewed-by: Kees Cook <kees@kernel.org>

-Kees

-- 
Kees Cook