vmlinux.o: warning: objtool: nmi_panic+0x30: unreachable instruction
From: kernel test robot
Date: Mon Aug 15 2022 - 01:08:30 EST
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 568035b01cfb107af8d2e4bd2fb9aea22cf5b868
commit: 2028a255f4df3af9e759f01f958d3237f825f256 x86/extable: Annotate ex_handler_msr_mce() as a dead end
date: 3 months ago
config: x86_64-randconfig-a006-20220815 (https://download.01.org/0day-ci/archive/20220815/202208151234.YgufKC9A-lkp@xxxxxxxxx/config)
compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
reproduce (this is a W=1 build):
# https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2028a255f4df3af9e759f01f958d3237f825f256
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout 2028a255f4df3af9e759f01f958d3237f825f256
# 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 where applicable
Reported-by: kernel test robot <lkp@xxxxxxxxx>
All warnings (new ones prefixed by >>):
>> vmlinux.o: warning: objtool: nmi_panic+0x30: unreachable instruction
objdump-func vmlinux.o nmi_panic:
0000 00000000000aeb50 <nmi_panic>:
0000 aeb50: f3 0f 1e fa endbr64
0004 aeb54: 55 push %rbp
0005 aeb55: 48 89 e5 mov %rsp,%rbp
0008 aeb58: 65 8b 15 00 00 00 00 mov %gs:0x0(%rip),%edx # aeb5f <nmi_panic+0xf> aeb5b: R_X86_64_PC32 cpu_number-0x4
000f aeb5f: b8 ff ff ff ff mov $0xffffffff,%eax
0014 aeb64: f0 0f b1 15 00 00 00 00 lock cmpxchg %edx,0x0(%rip) # aeb6c <nmi_panic+0x1c> aeb68: R_X86_64_PC32 panic_cpu-0x4
001c aeb6c: 83 f8 ff cmp $0xffffffff,%eax
001f aeb6f: 0f 84 00 00 00 00 je aeb75 <nmi_panic+0x25> aeb71: R_X86_64_PC32 .text.unlikely+0x886a
0025 aeb75: 39 c2 cmp %eax,%edx
0027 aeb77: 75 02 jne aeb7b <nmi_panic+0x2b>
0029 aeb79: 5d pop %rbp
002a aeb7a: c3 ret
002b aeb7b: e8 00 00 00 00 call aeb80 <nmi_panic+0x30> aeb7c: R_X86_64_PLT32 nmi_panic_self_stop-0x4
0030 aeb80: 5d pop %rbp
0031 aeb81: c3 ret
0032 aeb82: 66 66 2e 0f 1f 84 00 00 00 00 00 data16 cs nopw 0x0(%rax,%rax,1)
003d aeb8d: 0f 1f 00 nopl (%rax)
0000 000000000000886e <nmi_panic.cold>:
0000 886e: 48 c7 c7 00 00 00 00 mov $0x0,%rdi 8871: R_X86_64_32S .rodata.str1.1+0x8244
0007 8875: e8 00 00 00 00 call 887a <add_taint.cold> 8876: R_X86_64_PLT32 panic-0x4
--
0-DAY CI Kernel Test Service
https://01.org/lkp