Re: [PATCH 4.17 00/70] 4.17.3-stable review

From: Naresh Kamboju
Date: Mon Jun 25 2018 - 03:17:51 EST


>> Kselftest test case mov_ss_trap_64 is causing kernel panic on
>> qemu-system-x86_64 and PASS on real x86_64 hardware.
>>
>> [RUN] MOV SS; CSx14 INT3
>> [ 762.263790] PANIC: double fault, error_code: 0x0
>> [ 762.265169] CPU: 2 PID: 3380 Comm: mov_ss_trap_64 Not tainted 4.17.3-rc1 #1
>> [ 762.267588] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
>> BIOS 1.10.2-1 04/01/2014
>> [ 762.273190] RIP: 0010:error_entry+0x12/0x100
>>
>> Test code snippet,
>> main() {
>> <>
>> printf("[RUN]\tMOV SS; CS CS INT3\n");
>> asm volatile ("mov %[ss], %%ss; .byte 0x2e, 0x2e; int3" :: [ss] "m" (ss));
>> <>
>> }
>>
>> Reported upstream,
>> https://lkml.org/lkml/2018/6/25/19
>
> Nit, there is a better way to refer to lkml emails, see the bottom of
> this page as lots of time lkml.org does not work for people:
> https://www.kernel.org/lore.html

Sorry about that.

>
> This looks like a quemu bug, not a kernel issue, so did you tell the
> qemu developers about this?

Thanks for confirming this is not a kernel bug.
I will report this bug to qemu developer mailing list.

>
> In looking at the full headers:
> https://lore.kernel.org/lkml/CA+G9fYu0E0fM+WaFim1WKup5BZvjtGZ_4ii5FhTUjNZEqaAuwA@xxxxxxxxxxxxxx/
> it doesn't look like you did :(
>
> thanks,
>
> greg k-h