1.2 KiB
| layout | title | permalink |
|---|---|---|
| wiki | AssigningDevices | /wiki/AssigningDevices/ |
In order to assign a whole PCI/e device to a VM one should use qvm-pci tool. E.g.
lspci
Find the BDF address of the device you want to assign, and then:
qvm-pci -a <vmname> <bdf>
E.g. assuming 00:1a.0 is a BDF of the device I want to assign to "personal" domain:
qvm-pci -a personal 00:1a.0
Note that one can only assign full PCI or PCI Express devices. This means one cannot assign single USB devices -- only the whole USB controller with whatever USB devices connected to it. This limit is imposed by PC and VT-d architecture.
Possible issues
VM with PCI device in Qubes have allocated small buffer for DMA operations (called swiotlb). By default it is 2MB, but some devices needs a larger space. To change this allocation, edit VM kernel parameters (this is expressed in 512B chunks):
# qvm-prefs netvm |grep kernelopts
kernelopts : iommu=soft swiotlb=2048 (default)
# qvm-prefs -s netvm kernelopts "iommu=soft swiotlb=4096"
This is know to be needed for Realtek RTL8111DL Gigabit Ethernet Controller.