NVIDIA-SMI has failed because it couldn't communicate with the NVIDIA driver. Make sure that the lat

NVIDIA-SMI has failed because it couldn’t communicate with the NVIDIA driver. Make sure that the latest NVIDIA driver is installed and running.
解决办法：
cd /usr/src 查看驱动版本号(我的是396.18)
sudo apt-get install dkms
sudo dkms install -m nvidia -v 396.18
输入nvidia-smi

+-----------------------------------------------------------------------------+
| NVIDIA-SMI 396.18                 Driver Version: 396.18                    |
|-------------------------------+----------------------+----------------------+
| GPU  Name        Persistence-M| Bus-Id        Disp.A | Volatile Uncorr. ECC |
| Fan  Temp  Perf  Pwr:Usage/Cap|         Memory-Usage | GPU-Util  Compute M. |
|===============================+======================+======================|
|   0  Tesla M40 24GB      Off  | 00000000:04:00.0 Off |                    0 |
| N/A   35C    P0    58W / 250W |      0MiB / 22945MiB |      0%      Default |
+-------------------------------+----------------------+--------