1# SPDX-License-Identifier: GPL-2.0-only
2# ===========================================================================
3# Module final link
4# ===========================================================================
5
6PHONY := __modfinal
7__modfinal:
8
9include include/config/auto.conf
10include $(srctree)/scripts/Kbuild.include
11
12# for c_flags
13include $(srctree)/scripts/Makefile.lib
14
15# find all modules listed in modules.order
16modules := $(call read-file, $(MODORDER))
17
18__modfinal: $(modules:%.o=%.ko)
19	@:
20
21# modname and part-of-module are set to make c_flags define proper module flags
22modname = $(notdir $(@:.mod.o=))
23part-of-module = y
24
25quiet_cmd_cc_o_c = CC [M]  $@
26      cmd_cc_o_c = $(CC) $(filter-out $(CC_FLAGS_CFI), $(c_flags)) -c -o $@ $<
27
28%.mod.o: %.mod.c FORCE
29	$(call if_changed_dep,cc_o_c)
30
31ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
32
33quiet_cmd_ld_ko_o = LD [M]  $@
34      cmd_ld_ko_o +=							\
35	$(LD) -r $(KBUILD_LDFLAGS)					\
36		$(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE)		\
37		-T scripts/module.lds -o $@ $(filter %.o, $^);		\
38	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
39
40quiet_cmd_btf_ko = BTF [M] $@
41      cmd_btf_ko = 							\
42	if [ ! -f vmlinux ]; then					\
43		printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \
44	elif [ -n "$(CONFIG_RUST)" ] && $(srctree)/scripts/is_rust_module.sh $@; then 		\
45		printf "Skipping BTF generation for %s because it's a Rust module\n" $@ 1>&2; \
46	else								\
47		LLVM_OBJCOPY="$(OBJCOPY)" $(PAHOLE) -J $(PAHOLE_FLAGS) --btf_base vmlinux $@; \
48		$(RESOLVE_BTFIDS) -b vmlinux $@; 			\
49	fi;
50
51# Same as newer-prereqs, but allows to exclude specified extra dependencies
52newer_prereqs_except = $(filter-out $(PHONY) $(1),$?)
53
54# Same as if_changed, but allows to exclude specified extra dependencies
55if_changed_except = $(if $(call newer_prereqs_except,$(2))$(cmd-check),      \
56	$(cmd);                                                              \
57	printf '%s\n' 'savedcmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:)
58
59# Re-generate module BTFs if either module's .ko or vmlinux changed
60%.ko: %.o %.mod.o scripts/module.lds $(and $(CONFIG_DEBUG_INFO_BTF_MODULES),$(KBUILD_BUILTIN),vmlinux) FORCE
61	+$(call if_changed_except,ld_ko_o,vmlinux)
62ifdef CONFIG_DEBUG_INFO_BTF_MODULES
63	+$(if $(newer-prereqs),$(call cmd,btf_ko))
64endif
65
66targets += $(modules:%.o=%.ko) $(modules:%.o=%.mod.o)
67
68# Add FORCE to the prequisites of a target to force it to be always rebuilt.
69# ---------------------------------------------------------------------------
70
71PHONY += FORCE
72FORCE:
73
74# Read all saved command lines and dependencies for the $(targets) we
75# may be building above, using $(if_changed{,_dep}). As an
76# optimization, we don't need to read them if the target does not
77# exist, we will rebuild anyway in that case.
78
79existing-targets := $(wildcard $(sort $(targets)))
80
81-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
82
83.PHONY: $(PHONY)
84