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baastrup

Member

Registered: 2016-01-06

Posts: 9

vga passthrough on a laptop with kvm and vfio and no external monitor.

Hi.

Im trying to find a way to pass my desecrate card into a KVM VM with Windows 10 guest.
As I don't have an extra monitor I would like to use the laptops monitor when playing games in the VM.

Is this possible?

right now im trying in windowed mode with the following QEMU/KVM parametrers:  -vga qxl -sdl
But performance is not up to speed. (do to the fact that Windows 10 won't use the Nvidia card as no monitor is attached :-/ )

My laptop is a MSI gs60, with intel i915 and Nvidia GTX 970M

I managed to pass the GTX970M into the windows guest and was able to install the Nvidia drivers for it so it is recognized by Windows 10.

Any ideas?

Last edited by baastrup (2016-01-07 09:49:33)

baastrup

Member

Registered: 2016-01-06

Posts: 9

Re: vga passthrough on a laptop with kvm and vfio and no external monitor.

Would one of the following options be possible?

1. Make a fake windows 10 monitor and attached the Nvida gtx 970M to it. then use Steams stream in house service to the host?
2. Take over the laptop screen with some xrandr scripts, so the default output fron the Nvidia card would be displayed insted for the Intel i915?

Please help.

Last edited by baastrup (2016-01-07 09:47:43)

Lone_Wolf

Administrator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 15,162

Re: vga passthrough on a laptop with kvm and vfio and no external monitor.

2. Take over the laptop screen with some xrandr scripts, so the default output fron the Nvidia card would be displayed insted for the Intel i915?

Using passthrough the host doesn't see the nvidia card, telling xrandr to assign an output to a card it doesn't see should be impossible.

1 sounds like it could work.

---

Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

clean chroot building not flexible enough ?
Try clean chroot manager by graysky

baastrup

Member

Registered: 2016-01-06

Posts: 9

Re: vga passthrough on a laptop with kvm and vfio and no external monitor.

2. Take over the laptop screen with some xrandr scripts, so the default output fron the Nvidia card would be displayed insted for the Intel i915?

Using passthrough the host doesn't see the nvidia card, telling xrandr to assign an output to a card it doesn't see should be impossible.

1 sounds like it could work.

Then the next question, how  is option 1 done (google haven’t helped me yet)

Last edited by baastrup (2016-01-07 13:22:37)

izissise

Member

Registered: 2016-02-21

Posts: 1

Re: vga passthrough on a laptop with kvm and vfio and no external monitor.

Hello,
I currently trying to achieve exactly the same things, with the same computer and I'm a the same point (with windows 8.1 though).
I found this https://01.org/igvt-g/blogs/wangbo85/20 … ase-q32015 which might be a solution by sharing the intel gpu with the vm and then retrieving the nvidia gpu buffer from the vm. But I didn't tried much.

Tell me if you find anything

baastrup

Member

Registered: 2016-01-06

Posts: 9

Re: vga passthrough on a laptop with kvm and vfio and no external monitor.

I'm afraid optimus cards don't support VGA pass through so I gave up. I'm waiting on virgil3d where you can share the GPU instead.