1# SPDX-License-Identifier: GPL-2.0-only
  2
  3PHONY := __default
  4__default: __KEEPMAKEFILEO__B.o modules.builtin.modinfo modules.builtin
  5
  6include include/config/auto.conf
  7include $(srctree)/scripts/Kbuild.include
  8
  9# for objtool
 10include $(srctree)/scripts/Makefile.lib
 11
 12# Generate a linker script to ensure correct ordering of initcalls for Clang LTO
 13# ---------------------------------------------------------------------------
 14
 15quiet_cmd_gen_initcalls_lds = GEN     $@
 16      cmd_gen_initcalls_lds = \
 17	$(PYTHON3) $(srctree)/scripts/jobserver-exec \
 18	$(PERL) $(real-prereqs) > $@
 19
 20.tmp_initcalls.lds: $(srctree)/scripts/generate_initcall_order.pl \
 21		vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE
 22	$(call if_changed,gen_initcalls_lds)
 23
 24targets := .tmp_initcalls.lds
 25
 26ifdef CONFIG_LTO_CLANG
 27initcalls-lds := .tmp_initcalls.lds
 28endif
 29
 30# objtool for vmlinux.o
 31# ---------------------------------------------------------------------------
 32#
 33# For LTO and IBT, objtool doesn't run on individual translation units.
 34# Run everything on vmlinux instead.
 35
 36objtool-enabled := $(or $(delay-objtool),$(CONFIG_NOINSTR_VALIDATION))
 37
 38vmlinux-objtool-args-$(delay-objtool)			+= $(objtool-args-y)
 39vmlinux-objtool-args-$(CONFIG_GCOV_KERNEL)		+= --no-unreachable
 40vmlinux-objtool-args-$(CONFIG_NOINSTR_VALIDATION)	+= --noinstr \
 41							   $(if $(or $(CONFIG_MITIGATION_UNRET_ENTRY),$(CONFIG_MITIGATION_SRSO)), --unret)
 42
 43objtool-args = $(vmlinux-objtool-args-y) --link
 44
 45# Link of vmlinux.o used for section mismatch analysis
 46# ---------------------------------------------------------------------------
 47
 48vmlinux-o-ld-args-$(CONFIG_BUILTIN_MODULE_RANGES)	+= -Map=$@.map
 49
 50quiet_cmd_ld_vmlinux.o = LD      $@
 51      cmd_ld_vmlinux.o = \
 52	$(LD) ${KBUILD_LDFLAGS} -r -o $@ \
 53	$(vmlinux-o-ld-args-y) \
 54	$(addprefix -T , $(initcalls-lds)) \
 55	--whole-archive vmlinux.a --no-whole-archive \
 56	--start-group $(KBUILD_VMLINUX_LIBS) --end-group \
 57	$(cmd_objtool)
 58
 59define rule_ld_vmlinux.o
 60	$(call cmd_and_savecmd,ld_vmlinux.o)
 61	$(call cmd,gen_objtooldep)
 62endef
 63
 64vmlinux.o: $(initcalls-lds) vmlinux.a $(KBUILD_VMLINUX_LIBS) FORCE
 65	$(call if_changed_rule,ld_vmlinux.o)
 66
 67targets += vmlinux.o
 68
 69# module.builtin.modinfo
 70# ---------------------------------------------------------------------------
 71
 72OBJCOPYFLAGS_modules.builtin.modinfo := -j .modinfo -O binary
 73
 74targets += modules.builtin.modinfo
 75modules.builtin.modinfo: __KEEPMAKEFILEO__H.o FORCE
 76	$(call if_changed,objcopy)
 77
 78# module.builtin
 79# ---------------------------------------------------------------------------
 80
 81# The second line aids cases where multiple modules share the same object.
 82
 83quiet_cmd_modules_builtin = GEN     $@
 84      cmd_modules_builtin = \
 85	tr '\0' '\n' < $< | \
 86	sed -n 's/^[[:alnum:]:_]*\.file=//p' | \
 87	tr ' ' '\n' | uniq | sed -e 's:^:kernel/:' -e 's/$$/.ko/' > $@
 88
 89targets += modules.builtin
 90modules.builtin: modules.builtin.modinfo FORCE
 91	$(call if_changed,modules_builtin)
 92
 93# Add FORCE to the prerequisites of a target to force it to be always rebuilt.
 94# ---------------------------------------------------------------------------
 95
 96PHONY += FORCE
 97FORCE:
 98
 99# Read all saved command lines and dependencies for the $(targets) we
100# may be building above, using $(if_changed{,_dep}). As an
101# optimization, we don't need to read them if the target does not
102# exist, we will rebuild anyway in that case.
103
104existing-targets := $(wildcard $(sort $(targets)))
105
106-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
107
108.PHONY: $(PHONY)