Commit bede1696 authored by Masahiro Yamada's avatar Masahiro Yamada
Browse files

kbuild: enable objtool for *.mod.o and additional kernel objects 



Currently, objtool is disabled in scripts/Makefile.{modfinal,vmlinux}.

This commit moves rule_cc_o_c and rule_as_o_S to scripts/Makefile.lib
and set objtool-enabled to y there.

With this change, *.mod.o, .module-common.o,  builtin-dtb.o, and
vmlinux.export.o will now be covered by objtool.

Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
parent 000e22a8

scripts/Makefile.build

+0 −23
Original line number Diff line number Diff line
@@ -129,12 +129,6 @@ $(obj)/%.ll: $(obj)/%.c FORCE 


is-single-obj-m = $(and $(part-of-module),$(filter $@, $(obj-m)),y)



# When a module consists of a single object, there is no reason to keep LLVM IR.

# Make $(LD) covert LLVM IR to ELF here.

ifdef CONFIG_LTO_CLANG

cmd_ld_single_m = $(if $(is-single-obj-m), ; $(LD) $(ld_flags) -r -o $(tmp-target) $@; mv $(tmp-target) $@)

endif



ifdef CONFIG_MODVERSIONS

# When module versioning is enabled the following steps are executed:

# o compile a <file>.o from <file>.c
@@ -195,23 +189,6 @@ ifneq ($(findstring 1, $(KBUILD_EXTRA_WARN)),) 
cmd_warn_shared_object = $(if $(word 2, $(modname-multi)),$(warning $(kbuild-file): $*.o is added to multiple modules: $(modname-multi)))

endif



define rule_cc_o_c

	$(call cmd_and_fixdep,cc_o_c)

	$(call cmd,checksrc)

	$(call cmd,checkdoc)

	$(call cmd,gen_objtooldep)

	$(call cmd,gen_symversions_c)

	$(call cmd,record_mcount)

	$(call cmd,warn_shared_object)

endef



define rule_as_o_S

	$(call cmd_and_fixdep,as_o_S)

	$(call cmd,gen_objtooldep)

	$(call cmd,gen_symversions_S)

	$(call cmd,warn_shared_object)

endef



# Built-in and composite module parts

$(obj)/%.o: $(obj)/%.c $(recordmcount_source) FORCE

	$(call if_changed_rule,cc_o_c)

scripts/Makefile.lib

+25 −1
Original line number Diff line number Diff line
@@ -302,14 +302,38 @@ endef 
# ===========================================================================

# These are shared by some Makefile.* files.



objtool-enabled := y



ifdef CONFIG_LTO_CLANG

# objtool cannot process LLVM IR. Make $(LD) covert LLVM IR to ELF here.

cmd_ld_single = $(if $(objtool-enabled), ; $(LD) $(ld_flags) -r -o $(tmp-target) $@; mv $(tmp-target) $@)

endif



quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@

      cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< \

		$(cmd_ld_single_m) \

		$(cmd_ld_single) \

		$(cmd_objtool)



define rule_cc_o_c

	$(call cmd_and_fixdep,cc_o_c)

	$(call cmd,checksrc)

	$(call cmd,checkdoc)

	$(call cmd,gen_objtooldep)

	$(call cmd,gen_symversions_c)

	$(call cmd,record_mcount)

	$(call cmd,warn_shared_object)

endef



quiet_cmd_as_o_S = AS $(quiet_modtag)  $@

      cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< $(cmd_objtool)



define rule_as_o_S

	$(call cmd_and_fixdep,as_o_S)

	$(call cmd,gen_objtooldep)

	$(call cmd,gen_symversions_S)

	$(call cmd,warn_shared_object)

endef



# Copy a file

# ===========================================================================

# 'cp' preserves permissions. If you use it to copy a file in read-only srctree,

scripts/Makefile.modfinal

+2 −2
Original line number Diff line number Diff line
@@ -24,10 +24,10 @@ KCSAN_SANITIZE := n 
ccflags-remove-y := $(CC_FLAGS_CFI)



%.mod.o: %.mod.c FORCE

	$(call if_changed_dep,cc_o_c)

	$(call if_changed_rule,cc_o_c)



.module-common.o: $(srctree)/scripts/module-common.c FORCE

	$(call if_changed_dep,cc_o_c)

	$(call if_changed_rule,cc_o_c)



quiet_cmd_ld_ko_o = LD [M]  $@

      cmd_ld_ko_o =							\

scripts/Makefile.vmlinux

+2 −2
Original line number Diff line number Diff line
@@ -10,10 +10,10 @@ include $(srctree)/scripts/Makefile.lib 
targets :=



%.o: %.c FORCE

	$(call if_changed_dep,cc_o_c)

	$(call if_changed_rule,cc_o_c)



%.o: %.S FORCE

	$(call if_changed_dep,as_o_S)

	$(call if_changed_rule,as_o_S)



# Built-in dtb

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