On 28-02-19 23:29, Josh Poimboeuf wrote:
> On Thu, Feb 28, 2019 at 09:12:19PM +0100, Robin Meijboom wrote:
>> Hi Masahiro,
>>
>> On 28-02-19 14:36, Masahiro Yamada wrote:
>>> On Fri, Feb 15, 2019 at 11:15 AM Robin Meijboom <robin@xxxxxxxxxxxxx> wrote:
>>>>
>>>> Make clean currently does not remove the generated files for objtool:
>>>> tools/objtool/objtool, tools/objtool/fixdep, and
>>>> tools/objtool/arch/x86/lib/inat-tables.c.
>>>>
>>>> Clean these files up as part of make clean.
>>>>
>>>> Fixes: b9ab5ebb14ec ("objtool: Add CONFIG_STACK_VALIDATION option") and
>>>> bug report 199485 (https://bugzilla.kernel.org/show_bug.cgi?id=199485).
>>>>
>>>> Signed-off-by: Robin Meijboom <robin@xxxxxxxxxxxxx>
>>>> ---
>>>> In the discussions I didn't find a reason for keeping the files, so I
>>>> assume it is an oversight. Otherwise I would have expected them to be
>>>> removed at least by make distconfig (which they are not).
>>>>
>>>> Tested by compiling, cleaning, compiling again, and booting on x86_64.
>>>>
>>>> diff --git a/Makefile b/Makefile
>>>> index 141653226f3c..81a8149a805f 100644
>>>> --- a/Makefile
>>>> +++ b/Makefile
>>>> @@ -1328,6 +1328,8 @@ endif # CONFIG_MODULES
>>>>
>>>> # Directories & files removed with 'make clean'
>>>> CLEAN_DIRS += $(MODVERDIR) include/ksym
>>>> +CLEAN_FILES += tools/objtool/objtool tools/objtool/fixdep \
>>>> + tools/objtool/arch/$(ARCH)/lib/inat-tables.c
>>>>
>>>> # Directories & files removed with 'make mrproper'
>>>> MRPROPER_DIRS += include/config usr/include include/generated \
>>>>
>>>
>>>
>>>
Hi Josh,
Thanks for your feedback.
>>> I see the same artifacts are cleaned up by tools/objtool/Makefile:
>>>
>>> https://github.com/torvalds/linux/blob/v5.0-rc7/tools/objtool/Makefile#L59
>>>
>>>
>>> So, this patch proves the 'clean' target
>>> in tools/objtool/Makefile is useless.
>>>
>>
>> True. I believe this is because kbuild does not descend into that directory
>> as it does with the other directories. It works if you issue 'make clean'
>> from tools or tools/objtool.
>
> Right. Objtool is intended to be a standalone tool, though it's
> currently a bit kernel-specific. So a clean target within tools/objtool
> makes sense I think.
>
Clear. Currently objtool is also cleaned by the 'clean' target in
tools/Makefile. Would the above suggest that should be removed, or is it
fine as long as it is not in the top-level Makefile?
>>> BTW, 'make clean' must keep all the generated files
>>> that are needed to compile external modules.
>>>
>>> I guess cleaning objtool is wrong.
>>
>> I was considering the same. However, I did not find this in the discussions,
>> and as you pointed out the authors have included these items under the
>> 'make clean' target in tools/objtool/Makefile (which does not work for the
>> above reason).
>>
>> Additionally, if cleaning objtool is wrong, I would expect it to be at
>> least included in 'make distclean' or 'make mrproper' target (which it is
>> not).
>>
>> Josh, feel free to comment on the above.
>
> Objtool is needed for module builds, so it should *not* be removed with
> 'make clean' from the top-level directory.
>
> I guess it makes sense to remove it for mrproper (and by extension,
> distclean). Maybe mrproper could use tools/objtool's clean target
> somehow.
>
Since we have to use an exception anyway, my initial thought was to
use the 'standard exception' and include the artifacts in
MRPROPER_FILES. However, your idea is of course to _not_ have to
update the top-level Makefile every time you make a change to objtool
artifacts. I'm thinking about an elegant solution.
--
Kind regards,
Robin
