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VFIO-Tools

Tools Shell

VFIO-Tools

A collection of tools and scripts that aim to make PCI passthrough a little easier.
For more in-depth guides on how to use these tools, as well as PCI passthrough related news, benchmarks and tutorials, visit us on https://passthroughpo.st

libvirt_hooks

QEMU hook helper

This contains a hook-helper for libvirt which allows easier per-VM hooks.
Simply drop the qemu file in $SYSCONFDIR/libvirt/hooks/ (usually /etc/libvirt/hooks) and you’re ready to add hooks.
You can have a virtually limitless number of hook scripts per VM and per hook call, just keep in mind that a failed hook will prevent a VM from starting.
The way to add hooks is as follows:

  • Create a file in a path matching this structure: 
$SYSCONFDIR/libvirt/hooks/qemu.d/vm_name/hook_name/state_name/yourhook.conf
  • You can put anything you like in the hook, as long as you make sure you start your hook with a hashbang (i.e. #!/bin/bash).
  • When you’re done setting up your hook, run chmod +x on your hook file to make it executable.
  • If you’ve added the qemu hook helper file for the first time, you need to restart libvirt in order for it to be detected.

switch_displays.sh

This hook allows you to automatically switch your monitor input to your VM’s display.
To achieve this you need to have ddcutil installed and working and you need a DDC/CI capable monitor.
For a more detailed explanation and write-up, check out https://passthroughpo.st

vfioselect

vfio-pci helper

Makes assigning PCI devices to vfio-pci a bit easier, can generate modprobe rules, or bind a device to vfio-pci without needing to reboot. Requires dialog.

Usage: vfioselect [<arguments>]
  -t,--tmpfile  <path>   Specify path to temporary file
  -g,--genfile  <path>   Specify path to modprobe rule
  -o,--online            Attempt to bind/unbind without the need to reboot
  -h,--help              Display this help dialogue
  • vfioselect parses the rules that you define, if you have a rule already made, it is best to rename it to the default for vfioselect (vfioselect.conf), but a config file can be specified via -g /path/to/config.conf
  • If binding with a GPU shared between host and guest, it might be a good idea to use a qemu hook to switch input after the machine boots.

 
We enjoy creating these tools for the community and everything we make is completely free and open source — but developing them takes a lot of time and effort. Consider becoming a Patron to keep projects like these alive.



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