NAME
pciback —
Xen backend paravirtualized PCI
pass-through driver
SYNOPSIS
pciback* at pci?
DESCRIPTION
Thepciback driver is the backend part of the PCI
pass-through functionality that can be used by the Xen dom0 to export
pci(4)
devices to a guest domain. To export a PCI device to a guest domain, the
device has to be attached to pciback in the dom0.
When the guest domain is NetBSD, the
device attached to the pciback driver will attach to
a xpci(4) bus inside the guest domain.
EXAMPLES
To attach a device to the pciback driver,
follow these steps:
- look for the device PCI ID, via pcictl(8).
- edit boot.cfg(5) and add the PCI ID to the list of PCI IDs that
you want to attach to
pciback, in bus:device.function notation. The list is passed to dom0 module via thepciback.hideparameter:See also boot(8).pciback.hide=(bus:dev.fun)(bus:dev.func)(...) - reboot dom0.
- add the PCI ID to the list of PCI devices in the domain configuration
file:
pci = ['bus:dev.fun', '...'] - start the guest domain.
SEE ALSO
HISTORY
The pciback driver first appeared in
NetBSD 5.1.
AUTHORS
The pciback driver was written by
Manuel Bouyer
<bouyer@NetBSD.org>.
CAVEATS
Currently, to attach a device to the
pciback backend, this procedure has to be performed
at boot(8) time. In the future, it will be possible to do it without
requiring a dom0 reboot.
SECURITY CONSIDERATIONS
As PCI passthrough offers the possibility for guest domains to send arbitrary PCI commands to a physical device, this has direct impact on the overall stability and security of the system. For example, in case of erroneous or malicious commands, the device could overwrite physical memory portions, via DMA.