Chapter 16. SR-IOV
- Physical Functions (PFs) are full PCIe devices that include the SR-IOV capabilities. Physical Functions are discovered, managed, and configured as normal PCI devices. Physical Functions configure and manage the SR-IOV functionality by assigning Virtual Functions.
- Virtual Functions (VFs) are simple PCIe functions that only process I/O. Each Virtual Function is derived from a Physical Function. The number of Virtual Functions a device may have is limited by the device hardware. A single Ethernet port, the Physical Device, may map to many Virtual Functions that can be shared to guests.
SR-IOV devices can share a single physical port with multiple guests.
Live migration is presently unsupported. As with PCI passthrough, identical device configurations are required for live (and offline) migrations. Without identical device configurations, guest's cannot access the passed-through devices after migrating.