Unverified Commit fdb12c8a authored by Nathan Chancellor's avatar Nathan Chancellor
Browse files

kbuild: Leave objtool binary around with 'make clean' 



The difference between 'make clean' and 'make mrproper' is documented in
'make help' as:

  clean     - Remove most generated files but keep the config and
              enough build support to build external modules
  mrproper  - Remove all generated files + config + various backup files

After commit 68b4fe32 ("kbuild: Add objtool to top-level clean
target"), running 'make clean' then attempting to build an external
module with the resulting build directory fails with

  $ make ARCH=x86_64 O=build clean

  $ make -C build M=... MO=...
  ...
  /bin/sh: line 1: .../build/tools/objtool/objtool: No such file or directory

as 'make clean' removes the objtool binary.

Split the objtool clean target into mrproper and clean like Kbuild does
and remove all generated artifacts with 'make clean' except for the
objtool binary, which is removed with 'make mrproper'. To avoid a small
race when running the objtool clean target through both objtool_mrproper
and objtool_clean when running 'make mrproper', modify objtool's clean
up find command to avoid using find's '-delete' command by piping the
files into 'xargs rm -f' like the rest of Kbuild does.

Cc: stable@vger.kernel.org
Fixes: 68b4fe32 ("kbuild: Add objtool to top-level clean target")
Reported-by: default avatarMichal Suchanek <msuchanek@suse.de>
Closes: https://lore.kernel.org/20260225112633.6123-1-msuchanek@suse.de/


Reported-by: default avatarRainer Fiebig <jrf@mailbox.org>
Closes: https://lore.kernel.org/62d12399-76e5-3d40-126a-7490b4795b17@mailbox.org/


Acked-by: default avatarJosh Poimboeuf <jpoimboe@kernel.org>
Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarNicolas Schier <nsc@kernel.org>
Tested-by: default avatarNicolas Schier <nsc@kernel.org>
Link: https://patch.msgid.link/20260227-avoid-objtool-binary-removal-clean-v1-1-122f3e55eae9@kernel.org


Signed-off-by: default avatarNathan Chancellor <nathan@kernel.org>
parent 459cb3c0

Makefile

+4 −4
Original line number Diff line number Diff line
@@ -1497,13 +1497,13 @@ ifneq ($(wildcard $(resolve_btfids_O)),) 
	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean

endif



PHONY += objtool_clean

PHONY += objtool_clean objtool_mrproper



objtool_O = $(abspath $(objtree))/tools/objtool



objtool_clean:

objtool_clean objtool_mrproper:

ifneq ($(wildcard $(objtool_O)),)

	$(Q)$(MAKE) -sC $(abs_srctree)/tools/objtool O=$(objtool_O) srctree=$(abs_srctree) clean

	$(Q)$(MAKE) -sC $(abs_srctree)/tools/objtool O=$(objtool_O) srctree=$(abs_srctree) $(patsubst objtool_%,%,$@)

endif



tools/: FORCE
@@ -1686,7 +1686,7 @@ PHONY += $(mrproper-dirs) mrproper 
$(mrproper-dirs):

	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)



mrproper: clean $(mrproper-dirs)

mrproper: clean objtool_mrproper $(mrproper-dirs)

	$(call cmd,rmfiles)

	@find . $(RCS_FIND_IGNORE) \

		\( -name '*.rmeta' \) \

tools/objtool/Makefile

+5 −3
Original line number Diff line number Diff line
@@ -142,13 +142,15 @@ $(LIBSUBCMD)-clean: 
	$(Q)$(RM) -r -- $(LIBSUBCMD_OUTPUT)



clean: $(LIBSUBCMD)-clean

	$(call QUIET_CLEAN, objtool) $(RM) $(OBJTOOL)

	$(Q)find $(OUTPUT) -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete

	$(Q)find $(OUTPUT) \( -name '*.o' -o -name '\.*.cmd' -o -name '\.*.d' \) -type f -print | xargs $(RM)

	$(Q)$(RM) $(OUTPUT)arch/x86/lib/cpu-feature-names.c $(OUTPUT)fixdep

	$(Q)$(RM) $(OUTPUT)arch/x86/lib/inat-tables.c $(OUTPUT)fixdep

	$(Q)$(RM) -- $(OUTPUT)FEATURE-DUMP.objtool

	$(Q)$(RM) -r -- $(OUTPUT)feature



mrproper: clean

	$(call QUIET_CLEAN, objtool) $(RM) $(OBJTOOL)



FORCE:



.PHONY: clean FORCE
 
.PHONY: clean mrproper FORCE