Re: [ammarfaizi2-block:stable/linux-stable-rc/queue/5.15 146/150] kernel/futex.o: warning: objtool: futex_atomic_op_inuser()+0xb8: unreachable instruction

Josh Poimboeuf
2022-05-12T17:12:16Z

On Thu, May 12, 2022 at 10:17:09AM +0200, Peter Zijlstra wrote:
> On Thu, May 12, 2022 at 10:00:33AM +0800, kernel test robot wrote:
> > tree: https://github.com/ammarfaizi2/linux-block stable/linux-stable-rc/queue/5.15
> > head: 305e905f70311e1b49cc730931a19c3e364f4d8c
> > commit: 45dc9d706619a6814e4063d5431483f94badb5a1 [146/150] x86: Add straight-line-speculation mitigation
> > config: x86_64-randconfig-m001-20220509 (https://download.01.org/0day-ci/archive/20220512/202205120956.qLpGQurX-lkp@intel.com/config)
> > compiler: gcc-11 (Debian 11.2.0-20) 11.2.0
> > reproduce (this is a W=1 build):
> > # https://github.com/ammarfaizi2/linux-block/commit/45dc9d706619a6814e4063d5431483f94badb5a1
> > git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block
> > git fetch --no-tags ammarfaizi2-block stable/linux-stable-rc/queue/5.15
> > git checkout 45dc9d706619a6814e4063d5431483f94badb5a1
> > # save the config file
> > mkdir build_dir && cp config build_dir/.config
> > make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash
> >
> > If you fix the issue, kindly add following tag as appropriate
> > Reported-by: kernel test robot <lkp@intel.com>
> >
> > All warnings (new ones prefixed by >>):
> >
> > >> kernel/futex.o: warning: objtool: futex_atomic_op_inuser()+0xb8: unreachable instruction
> > --
> > >> mm/madvise.o: warning: objtool: madvise_behavior()+0x69: unreachable instruction
> > --
> > >> kernel/bpf/btf.o: warning: objtool: __btf_resolve_size()+0x72: unreachable instruction
>
> Would it be possible for the robot to include the output of this script:
>
> https://lkml.kernel.org/r/3eb3f091fd6bd9caba50392ceab98ce756804f3b.1650578171.git.jpoimboe@redhat.com

Ha, I already forgot about that script. I'll drop it into my
objtool/core branch (eventually for tip) unless anybody objects.

--
Josh