Re: [BUG REPORT] Triggering a panic in an x86 virtual machine does not wait
From: Thomas Gleixner
Date: Fri Jul 07 2023 - 06:18:56 EST
On Thu, Jul 06 2023 at 14:44, Baokun Li wrote:
> On 2023/7/5 16:59, Thomas Gleixner wrote:
>> + /*
>> + * If this is a crash stop which does not execute on the boot CPU,
>> + * then this cannot use the INIT mechanism because INIT to the boot
>> + * CPU will reset the machine.
>> + */
>> + if (this_cpu)
>> + return false;
> This patch does fix the problem of rebooting at panic, but the
> exported stack stays at stop_this_cpu() like below, instead of showing
> what the corresponding process is doing as before.
>
> PID: 681 TASK: ffff9ac2429d3080 CPU: 2 COMMAND: "fsstress"
> #0 [ffffb00200184fd0] stop_this_cpu at ffffffff89a4ffd8
> #1 [ffffb00200184fe8] __sysvec_reboot at ffffffff89a94213
> #2 [ffffb00200184ff0] sysvec_reboot at ffffffff8aee7491
> --- <IRQ stack> ---
> RIP: 0000000000000010 RSP: 0000000000000018 RFLAGS: ffffb00200f8bd08
> RAX: ffff9ac256fda9d8 RBX: 0000000009973a85 RCX: ffff9ac256fda078
> RDX: ffff9ac24416e300 RSI: ffff9ac256fda9e0 RDI: ffffffffffffffff
> RBP: ffff9ac2443a5f88 R8: 0000000000000000 R9: ffff9ac2422eeea0
> R10: ffff9ac256fda9d8 R11: 0000000000549921 R12: ffff9ac2422eeea0
> R13: ffff9ac251cd23c8 R14: ffff9ac24269a800 R15: ffff9ac251cd2150
> ORIG_RAX: ffffffff8a1719e4 CS: 0206 SS: ffffffff8a1719c8
> bt: WARNING: possibly bogus exception frame
>
> Do you know how this happened? I would be grateful if you could fix it.
No, I don't. But there is clearly a hint:
> bt: WARNING: possibly bogus exception frame
So the exception frame seems to be corrupted. I have no idea why.
The question is, whether this goes away when you revert that commit or not.
I can't oracle that out from your report.
Can you please revert 45e34c8af58f on top of Linus tree and verify that
it makes the issue go away?
Thanks,
tglx