If my system requires the latest Linux kernel to run the latest Nvidia proprietary drivers, is it possible for me not to install them on the host? (maybe use the open-source Noveau drivers, or install Intel on board graphics drivers on a more stable kernel for the distribution).

In the case above, would installing the latest kernel/Nvidia drivers on the guest distribution make full use of these drivers while the guest is in focus?

  • If hw passthrough is being used it means only the guest VM deals with the hw. – Rui F Ribeiro Aug 27 '17 at 9:40

If you passtrough some hardware to a guest system the host has no way of accessing it, in fact you need to blacklist nouveau/nvidia to make sure that the vfio driver can expose it to the VM.

Yes the VM will be able to make full use of the GPU, the performance impact will be extremely minor.

Also I'm not sure about what you mean by "in focus", only one VM can make use of the GPU at the same time and the host requires a reboot to use it.

Also note that if you're using an amd cpu there is currently a bug in the kvm implementation, if you enable npt(nested page tables) you may experience slowdown in some applications, and disabling it will reduce cpu performance of the guest, right now the only options are to either wait for a fix or using xen.

  • In that case, does it mean my host does not require any special packages or kernel versions at all, other than what is necessary to run kvm (with version that includes hardware passthrough)? This is surprising to me. Does my host even need x-server or Wayland in order to display what the guest wants? – Dean Kayton Aug 27 '17 at 14:09
  • No, it's as if the card were connected directly to the vm instead of the host computer, the card just needs to be bound to the vfio driver on the host. – Matt Aug 27 '17 at 14:14
  • But you still might want to have a secondary gpu on the host so that you can still access it if something goes wrong, a lot of intel processors have integrated gpus so that should not be a problem. – Matt Aug 27 '17 at 14:18

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.