Re: WARNING: CPU: 0 PID: 1752 at arch/x86/kernel/traps.c:788

From: Richard Weinberger
Date: Wed Jun 07 2017 - 03:36:25 EST


Andy, Paolo,

Am 07.06.2017 um 01:46 schrieb Paolo Bonzini:
>
>
> ----- Original Message -----
>> From: "Andy Lutomirski" <luto@xxxxxxxxxx>
>> To: "Richard Weinberger" <richard@xxxxxx>, "Paolo Bonzini" <pbonzini@xxxxxxxxxx>
>> Cc: "Andy Lutomirski" <luto@xxxxxxxxxx>, "linux-x86 64" <linux-x86_64@xxxxxxxxxxxxxxx>, linux-kernel@xxxxxxxxxxxxxxx,
>> "Thomas Meyer" <thomas@xxxxxxxx>
>> Sent: Wednesday, June 7, 2017 12:46:12 AM
>> Subject: Re: WARNING: CPU: 0 PID: 1752 at arch/x86/kernel/traps.c:788
>>
>> On Thu, Jun 1, 2017 at 3:46 PM, Richard Weinberger <richard@xxxxxx> wrote:
>>> Hi!
>>>
>>> UserModeLinux hits the following warning on the host.
>>> I've extracted the evil ptrace() command sequence, please see attached
>>> program,
>>> it triggers the warning too.
>>
>> This sounds like a known QEMU bug. Paolo, did this get fixed in QEMU?
>> If so, what version?
>
> If I understood what bug you are referring to, 2.9.0. Commit c52ab08aee
> ("target-i386: Fix eflags.TF/#DB handling of syscall/sysret insns", 2016-12-22).

This makes sense. I'll update my qemu and test again.

Thanks,
//richard