[ovirt-users] Is it possible to disable qxl video?

[Arman Khalatyan]

I just testing several GPUs with pci-passthrough: GTX630, Tesla 2050 and
FX5800.
None of them I got running with opengl/direct rendering inside the virtual
machine.
I was thinking something to do with qxl driver, but after blacklisting it
in the VMs kernel nothing was changed.
The VMs Xorg claiming always no display found even if I configure it with
headless option: nvidia-xconfig -a --use-display-device=None
--virtual=1280x1024
But with nvidia-smi I can see the GPU status, and I can run all cuda tests
where opengl/X11 is not involved.
My test system is CentOS 7 with ovirt 4.
BTW If I clone VM which was not running, to real host on bare metal,
everything is running as expecting.







***********************************************************

 Dr. Arman Khalatyan  eScience -SuperComputing
 Leibniz-Institut für Astrophysik Potsdam (AIP)
 An der Sternwarte 16, 14482 Potsdam, Germany

***********************************************************

On Mon, Jul 11, 2016 at 9:06 AM, Martin Polednik <mpolednik at redhat.com>
wrote:

> On 08/07/16 11:29 +0200, Michal Skrivanek wrote:
>
>>
>> On 06 Jul 2016, at 14:06, Francesco Romani <fromani at redhat.com> wrote:
>>>
>>>
>>> From: "Arman Khalatyan" <arm2arm at gmail.com>
>>> To: "users" <users at ovirt.org>
>>> Sent: Monday, July 4, 2016 11:52:24 AM
>>> Subject: [ovirt-users] Is it possible to disable qxl video?
>>>
>>>
>>> Hi,
>>> I am doing PCI Passthrough for GPUs.
>>> Is it possible somehow to disable/remove default video qxl?
>>> thanks,
>>> Arman,.
>>> Hi,
>>>
>>> The 4.0 Vdsm allows you to run a headless VM, meaning a VM without
>>> graphic device/frontend.
>>> Not sure Engine allows you that however.
>>>
>>
>> no it doesn’t
>>
>
> Even if engine allowed that, it may not be the correct solution.
>
> Running headless with PCI passthrough is considered primary VGA
> passthrough[1]. Using primary VGA passthrough without OVMF could cause
> (will cause) quite a bit of headaches.
>
> If you really want to try that, I assume using before_vm_start hook to
> remove the video device should be enough.
>
> [1] http://wiki.xenproject.org/wiki/Xen_VGA_Passthrough - it's
> possible to read about primary and secondary passthrough between the
> lines
>
> However, if QXL is the problem (why is that so?) then you can switch to
>> VGA(or CIRRUS if this is still 3.6)
>>
>> I'm afraid you will need to write a Vdsm hook.
>>>
>>> There could be simpler solutions depending on the Engine
>>>
>>> Bests,
>>>
>>> --
>>> Francesco Romani
>>> RedHat Engineering Virtualization R & D
>>> Phone: 8261328
>>> IRC: fromani
>>> _______________________________________________
>>> Users mailing list
>>> Users at ovirt.org <mailto:Users at ovirt.org>
>>> http://lists.ovirt.org/mailman/listinfo/users <
>>> http://lists.ovirt.org/mailman/listinfo/users>
>>>
>>
> _______________________________________________
>> Users mailing list
>> Users at ovirt.org
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>>
>
>
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