RHEL 6 Virtualization - 12.2. Adding a PCI device with virt-manager

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12.2. Adding a PCI device with virt-manager

PCI devices can be added to guests using the graphical virt-manager tool. The following procedure adds a 2 port USB controller to a virtualized guest.

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.

Record the PCI device number; the number is needed in other steps.

Detach the PCI device

Detach the device from the system.

# virsh nodedev-dettach pci_8086_3a6c 
Device pci_8086_3a6c dettached

Open the hardware settings

Open the virtual machine and click the Add Hardware button to add a new device to the guest.
Add the new device

Select Physical Host Device from the Hardware type list. Click Forward to continue.
Select a PCI device

Select an unused PCI device. Note that selecting PCI devices presently in use on the host causes errors. In this example a PCI to USB interface device is used.
Confirm the new device

Click the Finish button to confirm the device setup and add the device to the guest.

The setup is complete and the guest can now use the PCI device.

12.2. Adding a PCI device with virt-manager

Tip: determining the PCI device