Re: [PATCH v1 10/10] kconfig: Introduce OVERLAY= for make checkconfig

[Nicolas Schier <nsc@kernel.org>]

On Fri, Nov 06, 2026 at 10:19:22AM +0100, Ahmed S. Darwish wrote:
> For the kconfig checkconfig target, allow passing a rules overlay file
> through an OVERLAY= parameter.  This is mostly intended for distribution
> kernel packaging scripts, CI systems, and board support packages.
> 
> Document this parameter at the kernel's administration guide.
> 
> Note, the detailed overlay semantics are already explained at
> Documentation/tools/kconfig_checker.rst
> 
> Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
> ---
>  Documentation/admin-guide/README.rst | 7 ++++++-
>  scripts/kconfig/Makefile             | 6 ++++--
>  2 files changed, 10 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/admin-guide/README.rst b/Documentation/admin-guide/README.rst
> index 77ffe4dcb85b..b62689bcda6b 100644
> --- a/Documentation/admin-guide/README.rst
> +++ b/Documentation/admin-guide/README.rst
> @@ -263,7 +263,7 @@ The kconfig build system can validate the generated kernel ``.config``
>  against a selected rules profile. Running ``make checkconfig`` prints
>  usage information and the available profiles::
>  
> -  Usage: make RULES=<profile> checkconfig
> +  Usage: make RULES=<profile> [OVERLAY=<overlay>] checkconfig
>    Available RULES: preempt_rt
>  
>  For example, to validate the current configuration against the PREEMPT_RT
> @@ -278,6 +278,11 @@ selected rules profile. Each diagnostic includes a severity, such as
>  Apply the reported changes as needed and run ``make checkconfig`` again,
>  against the same rules, until no relevant diagnostics remain.
>  
> +The ``OVERLAY=`` parameter specifies an overlay file whose rules overrides
> +the built-in mainline profile selected by ``RULES=``. It is intended for
> +distributions kernel packaging scripts, CI systems, and board support
> +packages.
> +
>  For more information, see Documentation/tools/kconfig_checker.rst
>  
>  Compiling the kernel
> diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
> index d67a23730259..faaa8c16ab03 100644
> --- a/scripts/kconfig/Makefile
> +++ b/scripts/kconfig/Makefile
> @@ -126,6 +126,8 @@ testconfig: $(obj)/conf
>  clean-files += tests/.cache
>  
>  checkconfig := $(PYTHON3) -B $(srctree)/tools/kconfig-checker/check.py
> +checkconfig_overlay = $(if $(OVERLAY),-o "$(OVERLAY)")
> +
>  list_checkconfig_rules =						\
>  	echo -n >&2 "Available RULES: ";				\
>  	$(checkconfig) list-rules >&2;					\
> @@ -134,7 +136,7 @@ list_checkconfig_rules =						\
>  PHONY += checkconfig
>  checkconfig:
>  	$(Q)if [ -z "$(RULES)" ]; then					\
> -		echo >&2 "Usage: make RULES=<profile> checkconfig";	\
> +		echo >&2 "Usage: make RULES=<profile> [OVERLAY=<overlay>] checkconfig"; \
>  		$(list_checkconfig_rules);				\
>  		exit 2;							\
>  	fi
> @@ -143,7 +145,7 @@ checkconfig:
>  		$(list_checkconfig_rules);				\
>  		exit 2;							\
>  	fi
> -	$(Q)$(checkconfig) check -r "$(RULES)" -c "$(KCONFIG_CONFIG)"
> +	$(Q)$(checkconfig) check -r "$(RULES)" -c "$(KCONFIG_CONFIG)" $(checkconfig_overlay)

Please add the optional overlay arguments right here:

	$(Q)$(checkconfig) check -r "$(RULES)" -c "$(KCONFIG_CONFIG)" $(addprefix -o , "$(OVERLAY)")

<bike-shedding>
... or let kconfig-policy-checker read the 'OVERLAY' environment
variable itself.
</bike-shedding>


-- 
Nicolas