Howto gpu passthrough
bios settings
make sure you have virtualization support on in your bios:
for intel enable:
intel virtualization technology vt-d
for amd enable:
virtualization iommu
configure grub
add the following to /etc/default/grub:
for intel:
GRUB_CMDLINE_LINUX_DEFAULT="quiet ... intel_iommu=on"
for amd:
GRUB_CMDLINE_LINUX_DEFAULT="quiet ... amd_iommu=on"
- optional
If intel_iommu=on or amd_iommu=on works, you can try replacing them with intel_iommu=pt or amd_iommu=pt. The pt option only enables IOMMU for devices used in passthrough and will provide better host performance. However, the option may not be supported on all hardware. Revert to previous option if the pt option doesn't work for your host.
re-configure your grub:
grub-mkconfig -o /boot/grub/grub.cfg
isolating gpu
find the device id of the gpu:
lspci -nn |grep -E NVIDIA
command output:
1:00.0 VGA compatible controller [0300]: NVIDIA Corporation GA104 [GeForce RTX 3070] [10de:2484] (rev a1) 01:00.1 Audio device [0403]: NVIDIA Corporation GA104 High Definition Audio Controller [10de:228b] (rev a1)
edit /etc/modprobe.d/vfio.conf file and adding the following line with your ids:
options vfio-pci ids=10de:2484,10de:228b
if using the nvidia drivers add the following to /etc/default/grub:
GRUB_CMDLINE_LINUX_DEFAULT="vfio-pci.ids=10de:2484,10de:228b"
re-configure your grub:
grub-mkconfig -o /boot/grub/grub.cfg
edit /etc/mkinitcpio.conf and add the following:
MODULES="vfio vfio_iommu_type1 vfio_pci"
In the same file, also add modconf to the HOOKS line:
HOOKS="modconf"
backup your existing initramsfs image:
cp /boot/initramfs-linux.img /boot/default-initramfs-linux.img
rebuild initramfs:
mkinitcpio -g /boot/initramfs-linux.img -c /etc/mkinitcpio.conf
reboot your system:
reboot now
find your gpu and ensure that under “Kernel driver in use:” vfio-pci is displayed:
lspci -nnk
create bridge interface
create the bridge interface:
nmcli connection add type bridge autoconnect yes con-name br0 ifname br0
add device to bridge:
nmcli connection add type bridge-slave autoconnect yes con-name br0-eth0 ifname eth0 master br0
add ip address to bridge interface:
nmcli connection modify br0 ipv4.address 10.44.1.1/24 ipv4.method manual
active interfaces:
nmcli connection up br0 nmcli connection up br0-eth0
create script with iptables rules:
cat > /usr/local/bin/sharenetwlan << EOF #!/bin/bash echo "1" > /proc/sys/net/ipv4/ip_forward iptables -I INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT iptables -I FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT iptables -t nat -I POSTROUTING -o wlan0 -j MASQUERADE EOF
fix permissions:
chmod +x /usr/local/bin/sharenetwlan
add this script as systemd service:
cat > /etc/systemd/system/sharenetwlan.service << EOF [Unit] Description=Scream network pulse reciever After=NetworkManager.service Wants=NetworkManager.service [Service] Type=simple ExecStart=/usr/local/bin/sharenetwlan [Install] WantedBy=default.target EOF
reload systemd:
systemctl daemon-reload
start and enable service with systemd:
systemctl enable sharenetwlan.service systemctl start sharenetwlan.service
configure libvirtd
install virt-manager and ovmf:
pacman -S libvirt virt-manager ovmf qemu qemu-audio-pa
edit /etc/libvirt/qemu.conf and add the following:
nvram = [ "/usr/share/ovmf/x64/OVMF_CODE.fd:/usr/share/ovmf/x64/OVMF_VARS.fd" ]
add your username and libvirt group to /etc/libvirt/qemu.conf:
user = "linux" group = "libvirt"
start and enable libvirtd service:
systemctl start libvirtd.service systemctl enable libvirtd.service
start and enable virtlogd service:
systemctl start virtlogd.socket systemctl enable virtlogd.socket
add yourself to the libvirt group:
gpasswd -a username libvirt
install windows
install virtio windows drivers:
yay -S virtio-win
looking glass
add the following to your libvirt machine configuration inside the ‘devices’ section by running:
<shmem name='looking-glass'> <model type='ivshmem-plain'/> <size unit='M'>32</size> </shmem>
add virtio mouse:
<input type='mouse' bus='virtio'/>
add virtio keyboard:
<input type='keyboard' bus='virtio'/>
install looking glass client:
yay -S looking-glass
on windows download and install the looking glass host:
https://looking-glass.io/artifact/stable/host
additional xml configurations
for better performance, enable the hyper-v enlightenments:
<hyperv> <relaxed state="on"/> <vapic state="on"/> <spinlocks state="on" retries="8191"/> <vendor_id state="on" value="0123456789ab"/> <vpindex state='on'/> <runtime state="on"/> <synic state='on'/> <stimer state="on"> <direct state="on"/> </stimer> <reset state="on"/> <frequencies state="on"/> <reenlightenment state="on"/> <tlbflush state="on"/> <ipi state="on"/> <evmcs state="off"/> </hyperv>
disable memory ballooning:
<memballoon model="none"/>
cpu passthrough, cores and threads depends on your how many your cpu have:
<vcpu placement='static'>4</vcpu>
<cpu mode='host-passthrough' check='none' migratable='on'> <topology sockets='1' dies='1' cores='2' threads='2'/> <cache mode='passthrough'/> <feature policy='require' name='topoext'/> </cpu>
modify clock configuration:
<clock offset="localtime"> <timer name="rtc" tickpolicy="catchup"/> <timer name="pit" tickpolicy="delay"/> <timer name="hpet" present="no"/> <timer name="hypervclock" present="yes"/> <timer name="tsc" present="yes" mode="native"/> </clock>
for the above configuration your linux host must use tsc, check that using the following command:
cat /sys/devices/system/clocksource/*/current_clocksource
you should have the following result:
tsc
sound
use pulse audio to get sound, edit your vm and add the following:
|| make sure to change 1001 with your uid ||
<sound model='ich9'> <codec type='micro'/> <audio id='1'/> </sound> <audio id='1' type='pulseaudio' serverName='/run/user/1001/pulse/native'> <input mixingEngine='no'/> <output mixingEngine='no'/> </audio>
as root user copy your normal user pulse cookie to root profile:
mkdir -p ~/.config/pulse cp /home/linux/.config/pulse/cookie ~/.config/pulse/cookie
as root create the pulse audio client.conf:
cat > ~/.config/pulse/client.conf << EOF default-server = unix:/run/user/1001/pulse/native EOF