Well my problem is that I'm making VM for DisplayLink support (as my host OS is unsupported) and virtualized GPUs use modesetting driver in Linux guests which collides for some reason with DisplayLink USB dongles which use the same driver. So when VM has virtual gpu adapter then DisplayLink USB dongle doesn't work despite being passed through to guest. After disabling virtual gpu adapter DisplayLink dongle works properly in VM. I currently managed to get it to work in KVM+QEMU but I don't really like this solution as QEMU collides with VBox and in VBox but VBox has some security issues with USB passthrough so I'd feel better if it worked in Workstation. But well if it's not an option then I guess I'll accept what I have now.
