[stable:linux-5.4.y 4730/8053] arch/x86/kernel/cpu/mce/core.o: warning: objtool: ex_handler_rdmsr_fault()+0xf: unreachable instruction

[stable:linux-5.4.y 4730/8053] arch/x86/kernel/cpu/mce/core.o: warning: objtool: ex_handler_rdmsr_fault()+0xf: unreachable instruction

[kernel test robot]

Hi Thomas,

FYI, the error/warning was bisected to this commit, please ignore it if it's irrelevant.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-5.4.y
head:   32bea3bac5ca484c6f7e302c8c96fc686f62e7b4
commit: 0a0fbbd6cb654f748d87c0db10c31741101f2ab2 [4730/8053] x86/mce: Deduplicate exception handling
config: x86_64-rhel-8.3-ltp (https://download.01.org/0day-ci/archive/20230414/202304140009.FCTdOYcH-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-8) 11.3.0
reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/commit/?id=0a0fbbd6cb654f748d87c0db10c31741101f2ab2
        git remote add stable https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
        git fetch --no-tags stable linux-5.4.y
        git checkout 0a0fbbd6cb654f748d87c0db10c31741101f2ab2
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=x86_64 olddefconfig
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash M=arch/x86

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202304140009.FCTdOYcH-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> arch/x86/kernel/cpu/mce/core.o: warning: objtool: ex_handler_rdmsr_fault()+0xf: unreachable instruction


objdump-func vmlinux.o ex_handler_rdmsr_fault:
0000 000000000008c7e0 <ex_handler_rdmsr_fault>:
0000    8c7e0:	e8 00 00 00 00       	call   8c7e5 <ex_handler_rdmsr_fault+0x5>	8c7e1: R_X86_64_PLT32	__fentry__-0x4
0005    8c7e5:	48 89 f7             	mov    %rsi,%rdi
0008    8c7e8:	31 f6                	xor    %esi,%esi
000a    8c7ea:	e8 31 a8 ff ff       	call   87020 <ex_handler_msr_mce>
000f    8c7ef:	b8 01 00 00 00       	mov    $0x1,%eax
0014    8c7f4:	c3                   	ret
0015    8c7f5:	66 66 2e 0f 1f 84 00 00 00 00 00 	data16 cs nopw 0x0(%rax,%rax,1)

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests