kvm-guest-drivers-windows VS virtualbox-org-svn-vbox-trunk

There's mature VirtIO drivers for just about everything already, under the virtio-win umbrella: https://github.com/virtio-win/kvm-guest-drivers-windows

My desktop PC is using libvirt+qemu (on an Arch host. I use Arch, btw) to PCI passthru my RTX 4090 GPU to a Windows guest. I installed the guest initially with emulated SATA for the main drive. Once Windows was up and running, I installed virtio-win and the guest is now using virtIO accelerated drivers for the network interface, main disk. I'm also sharing some filesystems using virtio-fs.

So, I started configuring the PC with ubuntu desktop (since I need a GUI for my use case). Then I setup a windows KVM with this. In my use case, I want the windows VM to be always connected to a VPN (Mullvad) that has the toggle of LAN connections turned on. This is because I want to use sunshine on the KVM to stream my desktop to a firestick. This is how I have been configuring one PC till now for my family to be able to watch TV. The issue is that I cannot use sunshine or parsec cos there are no encoders in the VM, thus the performance sucks. (I could use software encoders, but I would use too much CPU for windows VM, which would make me unable to run a LLM (this was my plan) )

Note also: it just got an experimental Windows driver!

[1]https://github.com/virtio-win/kvm-guest-drivers-windows/pull...

virtio-GPU for Windows for now is just a basic display driver, without any kind of acceleration, so there shouldn't be any difference between using it and QXL, which is fully emulated and in it, if necessary, you can increase the VRAM to be able to use high resolutions, as explained here. Note: this link is just from a quick search, I tried this for myself some time ago but my intention was not to increase the resolution but just to find out if it was possible to have some kind of 3D acceleration, as it happens in VirtualBox, but is not possible yet.

The only sorta-responsive display tech I've found is Virt with GL (3D) enabled. And if your physical box has 4k video you can forget about going anywhere near full screen with that guest VM.

I suggest you open a new issue in the repository describing this, or search if there is one open reporting the same. Also, keep in mind that as an early stage it might be a good idea to avoid copying important files using this, you could end up losing data unless you do an integrity check (recently I tried installing a game on the VM in a host directory and it didn't work. I'm thinking of an alternative or going back to using VirtualBox, since the shared folders worked very well for this purpose).

The problem was really bad with latest virtio drivers, so I downgraded to version 204, as per: https://github.com/virtio-win/kvm-guest-drivers-windows/issues/623

So my understanding – if you run VirtualBox on macOS, and you choose macOS as Guest OS type when creating your VM, it automatically turns GetKeyFromRealSMC on. That means you are using option (2) by default. You can always switch to option (1) instead if you want to, but if you are virtualising macOS-on-macOS, there is little reason to.

From reading the VirtualBox source code [0] – it also automatically enables GetKeyFromRealSMC if it detects Apple hardware, even if the host OS isn't macOS. So, if you install Windows on your Mac, and then create a macOS VM in VirtualBox, it will automatically select option (2) as well. (I think, they actually include the code to talk to the Apple SMC in their Windows and Linux kernel drivers too.)

(Note I haven't actually tried doing this myself, this is just what I gather from the source.)

[0] https://github.com/mdaniel/virtualbox-org-svn-vbox-trunk/blo...