- ifneq ($(if $(KCONFIG),$(filter m,$(foreach c,$(filter-out %=y %=n %=m,$(KCONFIG)),$($(c)))),.),)
+ # check that all CONFIG_* symbols in $(KCONFIG) are set to 'm'
+ ifeq ($(filter-out m,$(foreach c,$(filter-out %=y %=n %=m,$(KCONFIG)),$(if $($(c)),$($(c)),n))),)