driverctl is a device driver control utility for Linux

Description

-----------

driverctl is a tool for manipulating and inspecting the system

device driver choices.

Devices are normally assigned to their sole designated kernel driver

by default. However in some situations it may be desireable to

override that default, for example to try an older driver to

work around a regression in a driver or to try an experimental alternative

driver. Another common use-case is pass-through drivers and driver

stubs to allow userspace to drive the device, such as in case of

virtualization.

driverctl integrates with udev to support overriding

driver selection for both cold- and hotplugged devices from the

moment of discovery, but can also change already assigned drivers,

assuming they are not in use by the system. The driver overrides

created by driverctl are persistent across system reboots

by default.

License

-------

Licensed under the GNU Lesser General Public License aka LGPL v2.1.

See COPYING for details.

Source repository

-----------------

git clone https://gitlab.com/driverctl/driverctl.git

System requirements

-------------------

- udev, tested with versions >= 219 but older versions are likely

  to work as well

- kernel >= 3.16 or backported support for driver_override device

  binding path:

  https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=782a985d7af26db39e86070d28f987cad21313c0

- bash-completion (optional)

Installation

------------

"make rpm" should create a working package to be installed for those on

rpm-based distros (tested on recent Fedora and RHEL 7), others should

be able to use "make install" (but note there's no "uninstall" target)

Usage

-----

Find devices currently driven by ixgbe driver:

# driverctl -v list-devices | grep ixgbe

0000:01:00.0 ixgbe (Ethernet 10G 4P X520/I350 rNDC)

0000:01:00.1 ixgbe (Ethernet 10G 4P X520/I350 rNDC)

Change them to use the vfio-pci driver:

# driverctl set-override 0000:01:00.0 vfio-pci

# driverctl set-override 0000:01:00.1 vfio-pci

Find devices with driver overrides:

# driverctl -v list-overrides

0000:01:00.0 vfio-pci (Ethernet 10G 4P X520/I350 rNDC)

0000:01:00.1 vfio-pci (Ethernet 10G 4P X520/I350 rNDC)

Find network devices:

# driverctl list-devices network

0000:01:00.0 ixgbe

0000:01:00.1 ixgbe

0000:06:00.0 igb

0000:06:00.1 igb

Remove the override from slot 0000:01:00.1:

# driverctl unset-override 0000:01:00.1

Extras

------

In addition to the actual driverctl utility, udev rules to expose

VFIO and UIO devices on systemd level are included to make them

dependable for services. 

Since the vfio device naming is based on IOMMU groups it is rather

unpredictable on the outset: for example on my laptop the NIC at

PCI slot 0000:00:19.0 would appear as /sys/devices/virtual/vfio/3

when bound to the vfio_pci driver. To make this more discoverable,

systemd aliases are added so the device is additionally addressable

by its PCI slot name, in this example it'd be:

sys-devices-pci0000:00-0000:00:19.0-vfio.device.

Contributing etc

----------------

Patches, bug reports and other feedback are welcome via the

project page: https://gitlab.com/driverctl/driverctl