Created attachment 302995 [details]
/proc/cpuinfo, .config

Hi,

when I start Xen 4.15.3 in efi with kernel 5.18.19, all works well;
but since kernel 5.19, I have a kernel panic on my /init process as
busybox symbolic link inside initramfs.

This is the kernel log :
...
[    6.265122] Run /init as init process
[    6.266027] traps: init[1] trap invalid opcode ip:5855d1 sp:7ffe5ceddeb0 error:0 in busybox[401000+1db000]
[    6.266553] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000004
[    6.267039] CPU: 3 PID: 1 Comm: init Tainted: G        W         5.19.0-dch #1
[    6.267522] Hardware name: Micro-Star International Co., Ltd. MS-7B84/B450M PRO-M2 (MS-7B84), BIOS 2.E0 06/12/2020
[    6.268010] Call Trace:
[    6.268495]  <TASK>
[    6.268974]  dump_stack_lvl+0x45/0x5e
[    6.269455]  panic+0x107/0x285
[    6.269923]  do_exit.cold+0x15/0x45
[    6.270389]  do_group_exit+0x28/0x90
[    6.270852]  get_signal+0x9f1/0xa40
[    6.271313]  arch_do_signal_or_restart+0x57/0x7b0
[    6.271771]  ? _raw_spin_unlock+0x10/0x30
[    6.272223]  ? finish_task_switch.isra.0+0x8e/0x270
[    6.272674]  ? __switch_to+0x186/0x400
[    6.273118]  exit_to_user_mode_prepare+0xc8/0x150
[    6.273564]  irqentry_exit_to_user_mode+0x5/0x20
[    6.274003]  asm_exc_invalid_op+0x16/0x20
[    6.274441] RIP: 0033:0x5855d1
[    6.274877] Code: f6 48 89 ef e8 90 79 03 00 48 c7 05 cd 2e 0c 00 01 00 00 00 48 89 2d 26 a2 0c 00 4c 8d 74 24 20 4c 8d 6c 24 40 4c 8d 64 24 18 <c5> f9 ef c0 48 b8 f6 75 ae 03 01 00 00 00 4c 8d 3d 8c 02 0a 00 c5
[    6.275776] RSP: 002b:00007ffe5ceddeb0 EFLAGS: 00010202
[    6.276221] RAX: 0000000000000000 RBX: 00000000004006c8 RCX: 0000000000000001
[    6.276670] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000648400
[    6.277116] RBP: 00000000009e0060 R08: 00007ffe5cfdf178 R09: 00000000effffef5
[    6.277561] R10: 0000000070000022 R11: 0000000000000032 R12: 00007ffe5ceddec8
[    6.278003] R13: 00007ffe5ceddef0 R14: 00007ffe5cedded0 R15: 000000006ffffeff
[    6.278442]  </TASK>
[    6.278903] Kernel Offset: disabled

I try to decode it :

All code
========
   0:   f6 48 89 ef             testb  $0xef,-0x77(%rax)
   4:   e8 90 79 03 00          call   0x37999
   9:   48 c7 05 cd 2e 0c 00    movq   $0x1,0xc2ecd(%rip)        # 0xc2ee1
  10:   01 00 00 00 
  14:   48 89 2d 26 a2 0c 00    mov    %rbp,0xca226(%rip)        # 0xca241
  1b:   4c 8d 74 24 20          lea    0x20(%rsp),%r14
  20:   4c 8d 6c 24 40          lea    0x40(%rsp),%r13
  25:   4c 8d 64 24 18          lea    0x18(%rsp),%r12
  2a:*  c5 f9 ef c0             vpxor  %xmm0,%xmm0,%xmm0                <-- trapping instruction
  2e:   48 b8 f6 75 ae 03 01    movabs $0x103ae75f6,%rax
  35:   00 00 00 
  38:   4c 8d 3d 8c 02 0a 00    lea    0xa028c(%rip),%r15        # 0xa02cb
  3f:   c5                      .byte 0xc5

Code starting with the faulting instruction
===========================================
   0:   c5 f9 ef c0             vpxor  %xmm0,%xmm0,%xmm0
   4:   48 b8 f6 75 ae 03 01    movabs $0x103ae75f6,%rax
   b:   00 00 00 
   e:   4c 8d 3d 8c 02 0a 00    lea    0xa028c(%rip),%r15        # 0xa02a1
  15:   c5                      .byte 0xc5

Regards,
Denis
PS:
   denis@srv2 ~ $ gcc --version
   gcc (Gentoo 11.3.0 p4) 11.3.0