[ovirt-users] Is it possible to disable qxl video?
Arman Khalatyan
arm2arm at gmail.com
Mon Jul 11 16:03:48 UTC 2016
Thanks for clarification. the kvm=off solved the problem.
NICE!!! I got now inside the VM:
OpenGL vendor string: NVIDIA Corporation
OpenGL renderer string: GeForce GT 630/PCIe/SSE2
OpenGL core profile version string: 4.4.0 NVIDIA 367.27
OpenGL core profile shading language version string: 4.40 NVIDIA via Cg
compiler
OpenGL core profile context flags: (none)
the steps to reproduce:
1) virsh edit render
2) change schema of xml: <domain type='kvm' xmlns:qemu='
http://libvirt.org/schemas/domain/qemu/1.0'>
3) add following in the end before </domain>:
<qemu:commandline>
<qemu:arg value='-cpu'/>
<qemu:arg value='host,kvm=off'/>
</qemu:commandline>
4) start vm, install nvidia driver, check gpu: nvidia smi
5) install virtualgl, init 3
6) nvidia-xconfig --enable-all-gpus --separate-x-screens
--use-display-device=None --virtual=1280x1024
init 5
7) vglconnet render01.vm and finally: vglrun glxinfo or whatever!!!
Now back to origin: how to add this tweak in to ovirt?? :)
***********************************************************
Dr. Arman Khalatyan eScience -SuperComputing
Leibniz-Institut für Astrophysik Potsdam (AIP)
An der Sternwarte 16, 14482 Potsdam, Germany
***********************************************************
On Mon, Jul 11, 2016 at 5:30 PM, Martin Polednik <mpolednik at redhat.com>
wrote:
> On 11/07/16 17:16 +0200, Arman Khalatyan wrote:
>
>> Yes I have a BusID inside the xorg.conf.
>> I just tested with virt-manager and indeed it is not a ovirt failure.
>> It is something to do with qemu-kvm + nvidia.
>> I found here:https://wiki.debian.org/VGAPassthrough that nvidia disables
>> device when it is running on qemu-kvm is it still the case? to overcome
>> that one need to set:
>>
>> -cpu host,kvm=off
>>
>> in the command line of qemu.
>>
>
> This applies to GPUs that NVIDIA does not support in virtualized
> environments (actually your GTX630). Quadro K2200 and higher
> (incl. grid, tesla) should not require masking the hypervisor. It
> could be worth to supply dmesg from the host and from the guest so we
> could see if there is any apparent failure.
>
> That being said, I have had failures even with supported card that
> just stopped at one point. It's worth trying the kvm=off trick.
>
> I was trying to convert virsh commands to qemu native, but it fails on
>> Centos 7 :(
>> virsh dumpxml > render.xml
>> virsh domxml-to-native qemu-argv render.xml
>> error: internal error: invalid PCI passthrough type 'default'
>>
>
> I usually take the qemu command line from
> /var/log/libvirt/qemu/${VM_NAME}, tweak it in vim and launch. Works
> even for oVirt VMs (if you can hack around the storage).
>
>
> ***********************************************************
>>
>> Dr. Arman Khalatyan eScience -SuperComputing
>> Leibniz-Institut für Astrophysik Potsdam (AIP)
>> An der Sternwarte 16, 14482 Potsdam, Germany
>>
>> ***********************************************************
>>
>> On Mon, Jul 11, 2016 at 11:55 AM, Martin Polednik <mpolednik at redhat.com>
>> wrote:
>>
>> On 11/07/16 09:46 +0000, Karli Sjöberg wrote:
>>>
>>>
>>>> Den 11 jul 2016 11:37 fm skrev Arman Khalatyan <arm2arm at gmail.com>:
>>>>
>>>>
>>>>> 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.
>>>>>
>>>>>
>>>> Don't remember If this was mentioned but have you tried doing the same
>>>> thing but with virt-manager on a standalone host, just to rule out oVirt
>>>> from the equation?
>>>>
>>>>
>>> Also, the xorg must be setup to use the VFIO GPU. There is BusID
>>> option in device section that must point to the guest address of the
>>> GPU. I'm not sure if you've done that (and I'm quite sure it's missing
>>> on the wiki, noted).
>>>
>>> [in the guest]
>>> $ lspci | grep VGA
>>> 03:00.0 VGA compatible controller: NVIDIA Corporation GM107GL [Quadro
>>> K2200] (rev a2)
>>>
>>> and using the address, add device section to /etc/X11/xorg.conf
>>>
>>> Section "Device"
>>> Identifier "Device0"
>>> Driver "nvidia"
>>> VendorName "NVIDIA Corporation"
>>> BusID "PCI:3:0:0"
>>> EndSection
>>>
>>> That should allow xorg to use the assigned GPU.
>>>
>>> mpolednik
>>>
>>>
>>> /K
>>>
>>>>
>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> ***********************************************************
>>>>>
>>>>> 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
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>>>>>>>> http://lists.ovirt.org/mailman/listinfo/users <
>>>>>>>> http://lists.ovirt.org/mailman/listinfo/users>
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>> _______________________________________________
>>>>>>
>>>>>>> Users mailing list
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>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>
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