MrSmiley381 wrote on 2020-03-16, 11:05:
So this board has two onboard ethernet ports, onboard video, and enough slots to make anybody happy. Is there a use case where you could build a couple of VM's and pass hardware to them directly? One ethernet port, a PCI Voodoo card, and a PCI sound card is enough to play Diablo II in its best possible form. That's assuming everything works, despite how impractical that would be. With all those USB ports you could add a couple of mouse/keyboard setups and build a few more VM's with passthrough hardware. Does a CGA card require DMA?
Most of my VM experience is limited to server hardware so I'd love for someone to more practically explain the sort of shenanigans this board enables.
The basic answer is that it's a Pain In The Arse, you'd be better using real or emulated hardware.
I wouldn't bet on being able to pass ISA through to any VM. Typically all PCI cards need to be passed through to the same VM as they share the same upsteam root port. PCI-e cards are constrained by which root ports they share (on a decent motherboard they can be passed through individually).
USB is awkward - onboard USB does not tend to pass through in a predictable manner, say if there's a six ports it may be in a 1/5 split. Add on USB cards either pass through the entire card, or if they work (the multi controller cards) they're expensive (150 UK pounds for a decent one..).
Then there's whether the OS drivers work well. Some cards are limited by design (Nvidia doesn't like you passing through consumer cards. The fact the OS is virtualised needs to be hidden in this case), others simply by poor drivers. Virtualised hardware is really only moderately similar to real hardware.