# SPDX-License-Identifier: GPL-2.0-only

PHONY := __default

__default: vmlinux.o

include include/config/auto.conf

include $(srctree)/scripts/Kbuild.include

# for objtool

include $(srctree)/scripts/Makefile.lib

# Generate a linker script to ensure correct ordering of initcalls for Clang LTO

# ---------------------------------------------------------------------------

quiet_cmd_gen_initcalls_lds = GEN $@

cmd_gen_initcalls_lds = \

$(PYTHON3) $(srctree)/scripts/jobserver-exec \

$(PERL) $(real-prereqs) > $@

.tmp_initcalls.lds: $(srctree)/scripts/generate_initcall_order.pl \

vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE

$(call if_changed,gen_initcalls_lds)

targets := .tmp_initcalls.lds

ifdef CONFIG_LTO_CLANG

initcalls-lds := .tmp_initcalls.lds

endif

# objtool for vmlinux.o

# ---------------------------------------------------------------------------

#

# For delay-objtool (IBT or LTO), objtool doesn't run on individual translation

# units. Instead it runs on vmlinux.o.

#

# For !delay-objtool + CONFIG_NOINSTR_VALIDATION, it runs on both translation

# units and vmlinux.o, with the latter only used for noinstr/unret validation.

objtool-enabled := $(or $(delay-objtool),$(CONFIG_NOINSTR_VALIDATION))

ifeq ($(delay-objtool),y)

vmlinux-objtool-args-y += $(objtool-args-y)

else

vmlinux-objtool-args-$(CONFIG_OBJTOOL_WERROR) += --werror

endif

vmlinux-objtool-args-$(CONFIG_NOINSTR_VALIDATION) += --noinstr \

$(if $(or $(CONFIG_MITIGATION_UNRET_ENTRY),$(CONFIG_MITIGATION_SRSO)), --unret)

objtool-args = $(vmlinux-objtool-args-y) --link

# Link of vmlinux.o used for section mismatch analysis

# ---------------------------------------------------------------------------

vmlinux-o-ld-args-$(CONFIG_BUILTIN_MODULE_RANGES) += -Map=$@.map

quiet_cmd_ld_vmlinux.o = LD $@

cmd_ld_vmlinux.o = \

$(LD) ${KBUILD_LDFLAGS} -r -o $@ \

$(vmlinux-o-ld-args-y) \

$(addprefix -T , $(initcalls-lds)) \

--whole-archive vmlinux.a --no-whole-archive \

--start-group $(KBUILD_VMLINUX_LIBS) --end-group \

$(cmd_objtool)

cmd_check_function_names = $(srctree)/scripts/check-function-names.sh $@

define rule_ld_vmlinux.o

$(call cmd_and_savecmd,ld_vmlinux.o)

$(call cmd,gen_objtooldep)

$(call cmd,check_function_names)

endef

vmlinux.o: $(initcalls-lds) vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE

$(call if_changed_rule,ld_vmlinux.o)

targets += vmlinux.o

# Add FORCE to the prerequisites of a target to force it to be always rebuilt.

# ---------------------------------------------------------------------------

PHONY += FORCE

FORCE:

# Read all saved command lines and dependencies for the $(targets) we

# may be building above, using $(if_changed{,_dep}). As an

# optimization, we don't need to read them if the target does not

# exist, we will rebuild anyway in that case.

existing-targets := $(wildcard $(sort $(targets)))

-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)

.PHONY: $(PHONY)