Hi Peter, On 25/05/22 01:20, Peter Zijlstra wrote: > On Tue, May 24, 2022 at 06:59:50PM +0000, Christophe Leroy wrote: >> >> Le 24/05/2022 à 20:02, Peter Zijlstra a écrit : >>> On Tue, May 24, 2022 at 08:01:39PM +0200, Peter Zijlstra wrote: >>>> On Tue, May 24, 2022 at 03:17:45PM +0200, Christophe Leroy wrote: >>>>> From: Sathvika Vasireddy >>>>> >>>>> This patch makes sure objtool runs only on the object files >>>>> that have ftrace enabled, instead of running on all the object >>>>> files. >>>>> >>>>> Signed-off-by: Naveen N. Rao >>>>> Signed-off-by: Sathvika Vasireddy >>>>> Signed-off-by: Christophe Leroy >>>>> --- >>>>> scripts/Makefile.build | 4 ++-- >>>>> 1 file changed, 2 insertions(+), 2 deletions(-) >>>>> >>>>> diff --git a/scripts/Makefile.build b/scripts/Makefile.build >>>>> index 2e0c3f9c1459..06ceffd92921 100644 >>>>> --- a/scripts/Makefile.build >>>>> +++ b/scripts/Makefile.build >>>>> @@ -258,8 +258,8 @@ else >>>>> # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file >>>>> # 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file >>>>> >>>>> -$(obj)/%.o: objtool-enabled = $(if $(filter-out y%, \ >>>>> - $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n),y) >>>>> +$(obj)/%.o: objtool-enabled = $(and $(if $(filter-out y%, $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n),y), \ >>>>> + $(if $(findstring $(strip $(CC_FLAGS_FTRACE)),$(_c_flags)),y),y) >>>> I think this breaks x86, quite a bit of files have ftrace disabled but >>>> very much must run objtool anyway. >>> Also; since the Changelog gives 0 clue as to what problem it's trying to >>> solve, I can't suggest anything. >> I asked Sathvika on the previous series, see >> https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20220523175548.922671-3-sv@linux.ibm.com/ >> >> He says it is to solve the problem I reported at >> https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20220318105140.43914-4-sv@linux.ibm.com/#2861128 > So on x86 we have: > > arch/x86/entry/vdso/Makefile:OBJECT_FILES_NON_STANDARD := y > > to kill objtool for the whole of the VDSO. When we run objtool on > vmlinux it isn't a problem, because the VDSO ends up as a data section > through linker scripts. Right.. Like you and Christophe mentioned, arch/powerpc/kernel/vdso/Makefile:OBJECT_FILES_NON_STANDARD := y should solve it for powerpc as well. I'll drop this patch and replace it with the above change as part of next revision series. Thanks for reviewing! - Sathvika