xref: /openbmc/linux/scripts/Makefile.modfinal (revision 6f4eaea2) 
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 and objtool_args
13include $(srctree)/scripts/Makefile.lib
14
15# find all modules listed in modules.order
16modules := $(sort $(shell cat $(MODORDER)))
17
18__modfinal: $(modules)
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) $(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
33ifdef CONFIG_LTO_CLANG
34# With CONFIG_LTO_CLANG, reuse the object file we compiled for modpost to
35# avoid a second slow LTO link
36prelink-ext := .lto
37
38# ELF processing was skipped earlier because we didn't have native code,
39# so let's now process the prelinked binary before we link the module.
40
41ifdef CONFIG_STACK_VALIDATION
42ifneq ($(SKIP_STACK_VALIDATION),1)
43cmd_ld_ko_o +=								\
44	$(objtree)/tools/objtool/objtool $(objtool_args)		\
45		$(@:.ko=$(prelink-ext).o);
46
47endif # SKIP_STACK_VALIDATION
48endif # CONFIG_STACK_VALIDATION
49
50endif # CONFIG_LTO_CLANG
51
52quiet_cmd_ld_ko_o = LD [M]  $@
53      cmd_ld_ko_o +=							\
54	$(LD) -r $(KBUILD_LDFLAGS)					\
55		$(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE)		\
56		-T scripts/module.lds -o $@ $(filter %.o, $^);		\
57	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
58
59quiet_cmd_btf_ko = BTF [M] $@
60      cmd_btf_ko = 							\
61	if [ -f vmlinux ]; then						\
62		LLVM_OBJCOPY=$(OBJCOPY) $(PAHOLE) -J --btf_base vmlinux $@; \
63	else								\
64		printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \
65	fi;
66
67# Same as newer-prereqs, but allows to exclude specified extra dependencies
68newer_prereqs_except = $(filter-out $(PHONY) $(1),$?)
69
70# Same as if_changed, but allows to exclude specified extra dependencies
71if_changed_except = $(if $(call newer_prereqs_except,$(2))$(cmd-check),      \
72	$(cmd);                                                              \
73	printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:)
74
75
76# Re-generate module BTFs if either module's .ko or vmlinux changed
77$(modules): %.ko: %$(prelink-ext).o %.mod.o scripts/module.lds $(if $(KBUILD_BUILTIN),vmlinux) FORCE
78	+$(call if_changed_except,ld_ko_o,vmlinux)
79ifdef CONFIG_DEBUG_INFO_BTF_MODULES
80	+$(if $(newer-prereqs),$(call cmd,btf_ko))
81endif
82
83targets += $(modules) $(modules:.ko=.mod.o)
84
85# Add FORCE to the prequisites of a target to force it to be always rebuilt.
86# ---------------------------------------------------------------------------
87
88PHONY += FORCE
89FORCE:
90
91# Read all saved command lines and dependencies for the $(targets) we
92# may be building above, using $(if_changed{,_dep}). As an
93# optimization, we don't need to read them if the target does not
94# exist, we will rebuild anyway in that case.
95
96existing-targets := $(wildcard $(sort $(targets)))
97
98-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
99
100.PHONY: $(PHONY)
101