nvidia-xorg.sh

#!/bin/bash -e
# This is a modified bit of code from https://github.com/selkies-project/docker-nvidia-glx-desktop/
# Specifically https://github.com/selkies-project/docker-nvidia-glx-desktop/blob/main/entrypoint.sh
# I have rmeoved some GUI apps, and the nvidia driver installer to isolat the xorg creation and xsession
# logic.

# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at https://mozilla.org/MPL/2.0/.

export SIZEW=1920
export SIZEH=1080
export REFRESH=60
export CDEPTH=24
export DPI=96
export VIDEO_PORT=DFP
export USERNAME="friend"


# Create and modify permissions of XDG_RUNTIME_DIR
sudo -u $USERNAME mkdir -pm700 /tmp/runtime-user
sudo chown $USERNAME:$USERNAME /tmp/runtime-user
sudo -u $USERNAME chmod 700 /tmp/runtime-user

# Make user directory owned by the user in case it is not
sudo chown $USERNAME:$USERNAME /home/$USERNAME

# This symbolic link enables running Xorg inside a container with `-sharevts`
sudo ln -snf /dev/ptmx /dev/tty7

# Start DBus without systemd
sudo /etc/init.d/dbus start

echo -e "allowed_users=anybody\nneeds_root_rights=yes" | sudo tee /etc/X11/Xwrapper.config > /dev/null

# Remove existing Xorg configuration
if [ -f "/etc/X11/xorg.conf" ]; then
  sudo rm -f "/etc/X11/xorg.conf"
fi

# Get first GPU device if all devices are available or `NVIDIA_VISIBLE_DEVICES` is not set
if [ "$NVIDIA_VISIBLE_DEVICES" == "all" ]; then
  export GPU_SELECT=$(sudo nvidia-smi --query-gpu=uuid --format=csv | sed -n 2p)
elif [ -z "$NVIDIA_VISIBLE_DEVICES" ]; then
  export GPU_SELECT=$(sudo nvidia-smi --query-gpu=uuid --format=csv | sed -n 2p)
# Get first GPU device out of the visible devices in other situations
else
  export GPU_SELECT=$(sudo nvidia-smi --id=$(echo "$NVIDIA_VISIBLE_DEVICES" | cut -d ',' -f1) --query-gpu=uuid --format=csv | sed -n 2p)
  if [ -z "$GPU_SELECT" ]; then
    export GPU_SELECT=$(sudo nvidia-smi --query-gpu=uuid --format=csv | sed -n 2p)
  fi
fi

if [ -z "$GPU_SELECT" ]; then
  echo "No NVIDIA GPUs detected or nvidia-container-toolkit not configured. Exiting."
  exit 1
fi

# Setting `VIDEO_PORT` to none disables RANDR/XRANDR, do not set this if using datacenter GPUs
if [ "${VIDEO_PORT,,}" = "none" ]; then
  export CONNECTED_MONITOR="--use-display-device=None"
# The X server is otherwise deliberately set to a specific video port despite not being plugged to enable RANDR/XRANDR, monitor will display the screen if plugged to the specific port
else
  export CONNECTED_MONITOR="--connected-monitor=${VIDEO_PORT}"
fi

# Bus ID from nvidia-smi is in hexadecimal format, should be converted to decimal format which Xorg understands, required because nvidia-xconfig doesn't work as intended in a container
HEX_ID=$(sudo nvidia-smi --query-gpu=pci.bus_id --id="$GPU_SELECT" --format=csv | sed -n 2p)
IFS=":." ARR_ID=($HEX_ID)
unset IFS
BUS_ID=PCI:$((16#${ARR_ID[1]})):$((16#${ARR_ID[2]})):$((16#${ARR_ID[3]}))
# A custom modeline should be generated because there is no monitor to fetch this information normally
export MODELINE=$(cvt -r "${SIZEW}" "${SIZEH}" "${REFRESH}" | sed -n 2p)
# Generate /etc/X11/xorg.conf with nvidia-xconfig
sudo nvidia-xconfig --virtual="${SIZEW}x${SIZEH}" --depth="$CDEPTH" --mode=$(echo "$MODELINE" | awk '{print $2}' | tr -d '"') --allow-empty-initial-configuration --no-probe-all-gpus --busid="$BUS_ID" --no-base-mosaic --only-one-x-screen ${CONNECTED_MONITOR}
# Guarantee that the X server starts without a monitor by adding more options to the configuration
sudo sed -i '/Driver\s\+"nvidia"/a\    Option         "ModeValidation" "NoMaxPClkCheck, NoEdidMaxPClkCheck, NoMaxSizeCheck, NoHorizSyncCheck, NoVertRefreshCheck, NoVirtualSizeCheck, NoExtendedGpuCapabilitiesCheck, NoTotalSizeCheck, NoDualLinkDVICheck, NoDisplayPortBandwidthCheck, AllowNon3DVisionModes, AllowNonHDMI3DModes, AllowNonEdidModes, NoEdidHDMI2Check, AllowDpInterlaced"\n    Option         "HardDPMS" "False"' /etc/X11/xorg.conf
# Add custom generated modeline to the configuration
sudo sed -i '/Section\s\+"Monitor"/a\    '"$MODELINE" /etc/X11/xorg.conf
# Prevent interference between GPUs, add this to the host or other containers running Xorg as well
echo -e "Section \"ServerFlags\"\n    Option \"AutoAddGPU\" \"false\"\nEndSection" | sudo tee -a /etc/X11/xorg.conf > /dev/null

# Default display is :0 across the container
export DISPLAY=":0"