I have pci passthrough working on my SH3210 motherboard for a VGA card, sound card, firewire and LAN. Unfortunately when I pass through the USB controllers and the VM boots, it hard resets the entire machine. Is anyone else experiencing problems, before I report this as a bug? Happens on unpatched 4.4 and -unstable I can work round this on 4.4 with host device passthrough (although this seems not to work in -unstable, currently?) But I'd prefer the whole controller. Also, where are iommu groups shown in Xen? There doesn't seem to be any enforcement of having go pass through an entire group of devices that aren't protected by ACS.