早起开机发现驱动掉了， 尝试重新安装驱动：
1.通过之前下载 run文件安装驱动一直失败；
2通过软件更新器安装驱动后黑屏无法进入系统，且键盘无效。
通过其他内核可以进入系统，安装驱动后报如下错误：
[drm:nv_drm_load [nvidia_drm]] ERROR [nvidia-drm] [GPU ID 0x00000800] Failed to allocate NvKmsKapiDevice [ 7.348371] kernel: [drm:nv_drm_probe_devices [nvidia_drm]] ERROR [nvidia-drm] [GPU ID 0x00000800] Failed to register device
且nvidia-smi提示无法找到设备。
no devices were found
通过命令lspci 查看设备，可以查看到显卡存在
01:00.0 VGA compatible controller: NVIDIA Corporation Device 2786 (rev a1)
于是尝试通过其他方法安装驱动：
通过ubuntu-drivers devices查看支持 驱动。
== /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0 ==
modalias : pci:v000010DEd00002786sv00007377sd00002000bc03sc00i00
vendor : NVIDIA Corporation
driver : nvidia-driver-535 - distro non-free recommended
driver : nvidia-driver-535-open - distro non-free
driver : nvidia-driver-545-open - distro non-free
driver : nvidia-driver-535-server-open - distro non-free
driver : nvidia-driver-545 - distro non-free
driver : nvidia-driver-535-server - distro non-free
driver : xserver-xorg-video-nouveau - distro free builtin
然后通过apt-get install nvidia-driver-535安装指定驱动。安装完成后，重启成功解决问题。
