Re: [PATCH] kbuild: Add vmlinux_install to facilitate debugging

[Masahiro Yamada]

On Tue, Oct 8, 2024 at 1:07 AM Zach Wade <zachwade.k@xxxxxxxxx> wrote:
>
> When testing multiple versions of the kernel with the same source code,it
> is often necessary to recompile the kernel, which is time-consuming for
> small hosts. I need to cp vmlinux to the corresponding module directory.
> I think adding this will make debugging the kernel a little more
> convenient.
>
> Signed-off-by: Zach Wade <zachwade.k@xxxxxxxxx>
> ---
>  Makefile | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
>
> diff --git a/Makefile b/Makefile
> index c5493c0c0ca1..1caab011599f 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -1579,6 +1579,7 @@ help:
>         @echo  '* vmlinux         - Build the bare kernel'
>         @echo  '* modules         - Build all modules'
>         @echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
> +       @echo  '  vmlinux_install - Install vmlinux to INSTALL_MOD_PATH (default: /)'
>         @echo  '  vdso_install    - Install unstripped vdso to INSTALL_MOD_PATH (default: /)'
>         @echo  '  dir/            - Build all files in dir and below'
>         @echo  '  dir/file.[ois]  - Build specified target only'
> @@ -1887,6 +1888,19 @@ modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \
>          $(if $(KBUILD_MODULES), modules_check)
>         $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
>
> +# ---------------------------------------------------------------------------
> +# vmlinux install
> +
> +PHONY += vmlinux_install
> +
> +vmlinux_install:
> +       @if [ -f vmlinux ]; then \
> +               echo "INSTALL ${MODLIB}/vmlinux"; \
> +               cp -f vmlinux ${MODLIB}/ ; \
> +       else \
> +               echo "vmlinux file does not exist."; \
> +       fi
> +

This is a very niche use-case.
What if someone else wants to copy vmlinux to /boot/
instead of ${MODLIB}/ ?

People tend to have local scripts to meet personal demands.
The upstream is not a place for that.


>  # Single targets
>  # ---------------------------------------------------------------------------
>  # To build individual files in subdirectories, you can do like this:
> --
> 2.46.0
>
>


-- 
Best Regards
Masahiro Yamada