Re: [PATCH v6 6/8] kbuild: Allow adding modules into the FIT ramdisk

[Nicolas Schier <nsc@kernel.org>]

On Thu, Nov 20, 2025 at 08:49:14AM +0100, Thomas Weißschuh wrote:
> On Wed, Nov 19, 2025 at 11:13:27AM -0700, Simon Glass wrote:
> > Support 'make image.fit FIT_MODULES=1' to put all the modules into a
> > ramdisk image within the FIT.
> > 
> > Add image.fit as a target which requires modules, so that modules will
> > built automatically when using FIT_MODULES is not empty.
> > 
> > Signed-off-by: Simon Glass <sjg@chromium.org>
> > Suggested-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> > Suggested-by: Reviewed-by: Nicolas Schier <nsc@kernel.org>
> > Acked-by: Nathan Chancellor <nathan@kernel.org>
> > ---
> > 
> > Changes in v6:
> > - Mention that FIT_MODULES just needs to be non-empty
> > - Make use of modules.order instead of using 'find'
> > 
> > Changes in v5:
> > - Build modules automatically if needed (fix from Nicolas Schier)
> > 
> > Changes in v4:
> > - Rename the Makefile variable from 'EXTRA' to 'MAKE_FIT_FLAGS'
> > - Use an empty FIT_MODULES to disable the feature, instead of '0'
> > - Make use of the 'modules' dependency to ensure modules are built
> > - Pass the list of modules to the script
> > 
> >  Makefile             | 1 +
> >  arch/arm64/Makefile  | 1 +
> >  scripts/Makefile.lib | 6 +++++-
> >  3 files changed, 7 insertions(+), 1 deletion(-)
> > 
> > diff --git a/Makefile b/Makefile
> > index 8cd46222fc48..4eccaef95826 100644
> > --- a/Makefile
> > +++ b/Makefile
> > @@ -773,6 +773,7 @@ endif
> >  # Just "make" or "make all" shall build modules as well
> >  
> >  modules-targets := all
> > +modules-targets += $(if $(FIT_MODULES),image.fit)
> >  modules-targets += modules
> >  modules-targets += nsdeps
> >  modules-targets += compile_commands.json
> > diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
> > index 73a10f65ce8b..7036f251ab40 100644
> > --- a/arch/arm64/Makefile
> > +++ b/arch/arm64/Makefile
> > @@ -174,6 +174,7 @@ endif
> >  all:	$(notdir $(KBUILD_IMAGE))
> >  
> >  image.fit: dtbs
> > +image.fit: $(if $(FIT_MODULES),modules)
> >  
> >  vmlinuz.efi image.fit: Image
> >  $(BOOT_TARGETS): vmlinux
> > diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> > index 1d581ba5df66..28e0cc0865b1 100644
> > --- a/scripts/Makefile.lib
> > +++ b/scripts/Makefile.lib
> > @@ -398,11 +398,15 @@ MAKE_FIT := $(srctree)/scripts/make_fit.py
> >  # Use this to override the compression algorithm
> >  FIT_COMPRESSION ?= gzip
> >  
> > +# Set this to non-empty to include an initrd with all the kernel modules
> > +FIT_MODULES ?=
> > +
> >  quiet_cmd_fit = FIT     $@
> >        cmd_fit = $(MAKE_FIT) -o $@ --arch $(UIMAGE_ARCH) --os linux \
> > -		--name '$(UIMAGE_NAME)' \
> > +		--name '$(UIMAGE_NAME)' $(MAKE_FIT_FLAGS) \
> 
> Remnant of a previous revision?
> 
> >  		$(if $(findstring 1,$(KBUILD_VERBOSE)),-v) \
> >  		$(if $(FIT_DECOMPOSE_DTBS),--decompose-dtbs) \
> > +		$(if $(FIT_MODULES),--modules @$(objtree)/modules.order) \
> 
> I am wondering how module dependencies work without the depmod invocation
> and modules.dep file.

oh, good point.  Stripping and signing and module compression is also
done during 'modules_install'.


-- 
Nicolas