Re: [Qemu-devel] E5-2620v2 - emulation stop error

Andrey Korolyov
2015-03-27T10:17:07Z

On Fri, Mar 27, 2015 at 12:03 AM, Bandan Das <bsd@redhat.com> wrote:
> Radim Krčmář <rkrcmar@redhat.com> writes:
>
>> 2015-03-26 21:24+0300, Andrey Korolyov:
>>> On Thu, Mar 26, 2015 at 8:40 PM, Radim Krčmář <rkrcmar@redhat.com> wrote:
>>> > 2015-03-26 20:08+0300, Andrey Korolyov:
>>> >> KVM internal error. Suberror: 2
>>> >> extra data[0]: 800000ef
>>> >> extra data[1]: 80000b0d
>>> >
>>> > Btw. does this part ever change?
>>> >
>>> > I see that first report had:
>>> >
>>> > KVM internal error. Suberror: 2
>>> > extra data[0]: 800000d1
>>> > extra data[1]: 80000b0d
>>> >
>>> > Was that a Windows guest by any chance?
>>>
>>> Yes, exactly, different extra data output was from a Windows VMs.
>>
>> Windows uses vector 0xd1 for timer interrupts.
>
>> I second Bandan -- checking that it reproduces on other machine would be
>> great for sanity :) (Although a bug in our APICv is far more likely.)
>
> If it's APICv related, a run without apicv enabled could give more hints.
>
> Your "devices not getting reset" hypothesis makes the most sense to me,
> maybe the timer vector in the error message is just one part of
> the whole story. Another misbehaving interrupt from the dark comes in at the
> same time and leads to a double fault.

Default trace (APICv enabled, first reboot introduced the issue):
http://xdel.ru/downloads/kvm-e5v2-issue/hanged-reboot-apic-on.dat.gz

Trace without APICv (three reboots, just to make sure to hit the
problematic condition of supposed DF, as it still have not one hundred
percent reproducibility):
http://xdel.ru/downloads/kvm-e5v2-issue/apic-off.dat.gz

It would be great of course to reproduce this somewhere else,
otherwise all this thread may end in fixing a bug which exists only at
my particular platform. Right now I have no hardware except a lot of
well-known (in terms of existing issues) Supermicro boards of one
model.