Installation guide

Chapter 12. PCI passthrough
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3. Ready to use
Reboot the system to enable the changes. Your system is now PCI passthrough capable.
Procedure 12.2. Preparing an AMD system for PCI passthrough
• Enable AMD IOMMU extensions
The AMD IOMMU extensions are required for PCI passthrough with Red Hat Enterprise Linux.
The extensions must be enabled in the BIOS. Some system manufacturers disable these
extensions by default.
AMD systems only require that the IOMMU is enabled in the BIOS. The system is ready for PCI
passthrough once the IOMMU is enabled.
12.1. Adding a PCI device with virsh
These steps cover adding a PCI device to a virtualized guest on a KVM hypervisor using hardware-
assisted PCI passthrough.
This example uses a USB controller device with the PCI identifier code, pci_8086_3a6c, and a fully
virtualized guest named win2k3.
1. Identify the device
Identify the PCI device designated for passthrough to the guest. The virsh nodedev-list
command lists all devices attached to the system. The --tree option is useful for identifying
devices attached to the PCI device (for example, disk controllers and USB controllers).
# virsh nodedev-list --tree
For a list of only PCI devices, run the following command:
# virsh nodedev-list | grep pci
In the output from this command, each PCI device is identified by a string, as shown in the
following example output:
pci_0000_00_00_0
pci_0000_00_02_0
pci_0000_00_02_1
pci_0000_00_03_0
pci_0000_00_03_2
pci_0000_00_03_3
pci_0000_00_19_0
pci_0000_00_1a_0
pci_0000_00_1a_1
pci_0000_00_1a_2
pci_0000_00_1a_7
pci_0000_00_1b_0
pci_0000_00_1c_0
Tip: determining the PCI device
Comparing lspci output to lspci -n (which turns off name resolution) output can assist in
deriving which device has which device identifier code.