Re: [kbuild-all] Re: [ebiederm-user-namespace:signal-for-v5.17 4/12] arch/x86/kernel/dumpstack.o: warning: objtool: oops_end() falls through to next function show_opcodes()

[Rong Chen]

On 12/15/21 01:29, Eric W. Biederman wrote:
> kernel test robot <lkp@xxxxxxxxx> writes:
>
> > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git signal-for-v5.17
> > head:   6b1248798eb6f6d5285db214299996ecc5dc1e6b
> > commit: 0e25498f8cd43c1b5aa327f373dd094e9a006da7 [4/12] exit: Add and use make_task_dead.
> > config: x86_64-randconfig-a011-20211213 (https://download.01.org/0day-ci/archive/20211214/202112140949.Uq5sFKR1-lkp@xxxxxxxxx/config)
> > compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
> > reproduce (this is a W=1 build):
> >          # https://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git/commit/?id=0e25498f8cd43c1b5aa327f373dd094e9a006da7
> >          git remote add ebiederm-user-namespace https://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git
> >          git fetch --no-tags ebiederm-user-namespace signal-for-v5.17
> >          git checkout 0e25498f8cd43c1b5aa327f373dd094e9a006da7
> >          # save the config file to linux build tree
> >          mkdir build_dir
> >          make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash arch/x86/kernel/ kernel/ lib/kunit/
> >
> > If you fix the issue, kindly add following tag as appropriate
> > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> >
> > All warnings (new ones prefixed by >>):
> >
> > > > lib/kunit/kunit-example-test.o: warning: objtool: .text.unlikely: unexpected end of section
> > --
> > > > arch/x86/kernel/dumpstack.o: warning: objtool: oops_end() falls through to next function show_opcodes()
> I am confused.  This change patches objtool to rename
> rewind_stack_and_do_exit to rewind_stack_and_make_dead in the list
> global_noreturns in tools/objtool/check.c
>
> There is no other change to oops_end other than that renaming.
>
> Did the robot somehow mange to run an old version of objtool while
> building and this get this error?
>
> I tried and I am not currently able to reproduce this error.  Do you
> have any additional pointers on how I might reproduce this?

Hi Eric,

The reproduce step in report based on a full build, I can reproduce the 
warnings with the below command:

  make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash

Best Regards,
Rong Chen