debian12 系统 开机自动加载 nvidia-uvm

debian 系统不知为何，开机没有自动加载 nvidia-uvm 设备，需要在主机系统手动启动任意一个cuda程序才能加载，非常坑爹。

写了一个脚本，配置了一个自动创建 nvidia-uvm 的 systemd 的服务。

#!/bin/bash

# 确保为 root 用户
if [ "$UID" -ne "0" ]; then
	echo "Must be root to run this script."
	exit 1
fi


# 创建自动加载脚本
echo "Create preload-nv-mod.sh > /preload_nv_mod.sh"
cat << \EOF > /preload_nv_mod.sh 
#!/bin/bash

/sbin/modprobe nvidia

if [ "$?" -eq 0 ]; then
  # Count the number of NVIDIA controllers found.
  NVDEVS=`lspci | grep -i NVIDIA`
  N3D=`echo "$NVDEVS" | grep "3D controller" | wc -l`
  NVGA=`echo "$NVDEVS" | grep "VGA compatible controller" | wc -l`

  N=`expr $N3D + $NVGA - 1`
  for i in `seq 0 $N`; do
    mknod -m 666 /dev/nvidia$i c 195 $i
  done

  mknod -m 666 /dev/nvidiactl c 195 255

else
  exit 1
fi

/sbin/modprobe nvidia-uvm

if [ "$?" -eq 0 ]; then
  # Find out the major device number used by the nvidia-uvm driver
  D=`grep nvidia-uvm /proc/devices | awk '{print $1}'`

  mknod -m 666 /dev/nvidia-uvm c $D 0
else
  exit 1
fi

EOF

# 设定 755 权限
chown root:root /preload_nv_mod.sh
chmod 755 /preload_nv_mod.sh


# 创建 systemd 的服务配置文件
echo "Create preload-nv-mod.service > /lib/systemd/system/preload-nv-mod.service"

cat << \EOF > /lib/systemd/system/preload-nv-mod.service
[Unit]
Description=preload-nv-mod
Documentation=None
ConditionFileIsExecutable=/preload_nv_mod.sh
After=network.target

[Service]
Type=forking
ExecStart=/preload_nv_mod.sh
TimeoutSec=0
RemainAfterExit=yes
GuessMainPID=no

[Install]
WantedBy=multi-user.target

EOF

# 设定服务配置的权限
chown root:root /lib/systemd/system/preload-nv-mod.service
chmod 644 /lib/systemd/system/preload-nv-mod.service

# 启用服务
echo "setting autostart"
systemctl enable preload-nv-mod
# 启动服务
echo "start service"
systemctl start preload-nv-mod
# 检查服务状态
echo "check service status"
systemctl status preload-nv-mod

参考资料
nvidia cuda官方创建 nvidia-uvm 节点的脚本
https://docs.nvidia.com/cuda/cuda-installation-guide-linux/index.html#runfile-verifications

stackoverflow 上的问题 正确创建 nvidia-uvm 设备
https://askubuntu.com/questions/590319/how-do-i-enable-automatically-nvidia-uvm

Debian11 创建 systemd 开机服务
https://www.burning.net.cn/article/article-60