不久前，我添加了graphics-driversPPA 并安装了 415 驱动程序。我决定返回到我原来的驱动程序 390，但似乎犯了一个错误 - 我在切换之前删除了 PPA。当我尝试从 415 切换到 390 时，我收到了一条错误消息（我不记得确切的消息，但它提到了缓存）。
使用 390 驱动程序时，我无法选择 NVIDIA prime。如果我这样做，我发现：
- 我的系统无法正常启动到桌面，而是卡在 Ubuntu 加载徽标和终端之间的短暂循环中，终端上反复出现以下内容，最后出现黑屏：
启动 NVIDIA 持久守护进程
停止 NVIDIA 持久守护进程
- 使用某些 NVIDIA 工具会导致屏幕挂起。例如，如果我使用
nvidia-settings，屏幕会冻结。如果我使用nvidia-bug-report.sh，系统会冻结，仅生成以下内容nvidia-bug-report.log.gz：
。
____________________________________________
Start of NVIDIA bug report log file. Please include this file, along
with a detailed description of your problem, when reporting a graphics
driver bug via the NVIDIA Linux forum (see devtalk.nvidia.com)
or by sending email to '[email protected]'.
nvidia-bug-report.sh Version: 23805530
Date: Wed 27 Feb 02:08:52 GMT 2019
uname: Linux u-rdm 4.18.0-15-generic #16~18.04.1-Ubuntu SMP Thu Feb 7 14:06:04 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
command line flags:
当我运行时lspci -v，与图形相关的条目似乎如下：
00:02.0 VGA compatible controller: Intel Corporation UHD Graphics 620 (rev 07) (prog-if 00 [VGA controller])
Subsystem: Dell UHD Graphics 620
Flags: bus master, fast devsel, latency 0, IRQ 130
Memory at d4000000 (64-bit, non-prefetchable) [size=16M]
Memory at b0000000 (64-bit, prefetchable) [size=256M]
I/O ports at f000 [size=64]
[virtual] Expansion ROM at 000c0000 [disabled] [size=128K]
Capabilities: <access denied>
Kernel driver in use: i915
Kernel modules: i915
01:00.0 3D controller: NVIDIA Corporation GM108M [GeForce 940MX] (rev a2)
Subsystem: Dell GM108M [GeForce 940MX]
Flags: bus master, fast devsel, latency 0, IRQ 142
Memory at d2000000 (32-bit, non-prefetchable) [size=16M]
Memory at c0000000 (64-bit, prefetchable) [size=256M]
Memory at d0000000 (64-bit, prefetchable) [size=32M]
I/O ports at e000 [size=128]
Expansion ROM at d3000000 [disabled] [size=512K]
Capabilities: <access denied>
Kernel driver in use: nouveau
Kernel modules: nvidiafb, nouveau, nvidia_drm, nvidia
如果我运行glxinfo，则没有对 NVIDIA 的引用。它似乎与集成显卡一起使用：
OpenGL vendor string: Intel Open Source Technology Center
OpenGL renderer string: Mesa DRI Intel(R) UHD Graphics 620 (Kabylake GT2)
当问题首次出现时，我记得尝试清除并重新安装 NVIDIA 软件包，但无济于事。
我注意到，运行lsmod，没有出现nvidiafb提到的模块lspci。此外，运行sudo modprobe nvidia会产生以下内容导致系统挂起。
目前，dpkg -l | grep nvidia给出以下输出：
ii libnvidia-cfg1-390:amd64 390.77-0ubuntu0.18.04.2 amd64 NVIDIA binary OpenGL/GLX configuration library
ii libnvidia-common-390 390.77-0ubuntu0.18.04.2 all Shared files used by the NVIDIA libraries
ii libnvidia-compute-390:amd64 390.77-0ubuntu0.18.04.2 amd64 NVIDIA libcompute package
ii libnvidia-compute-390:i386 390.77-0ubuntu0.18.04.2 i386 NVIDIA libcompute package
ii libnvidia-decode-390:amd64 390.77-0ubuntu0.18.04.2 amd64 NVIDIA Video Decoding runtime libraries
ii libnvidia-decode-390:i386 390.77-0ubuntu0.18.04.2 i386 NVIDIA Video Decoding runtime libraries
ii libnvidia-encode-390:amd64 390.77-0ubuntu0.18.04.2 amd64 NVENC Video Encoding runtime library
ii libnvidia-encode-390:i386 390.77-0ubuntu0.18.04.2 i386 NVENC Video Encoding runtime library
ii libnvidia-fbc1-390:amd64 390.77-0ubuntu0.18.04.2 amd64 NVIDIA OpenGL-based Framebuffer Capture runtime library
ii libnvidia-fbc1-390:i386 390.77-0ubuntu0.18.04.2 i386 NVIDIA OpenGL-based Framebuffer Capture runtime library
ii libnvidia-gl-390:amd64 390.77-0ubuntu0.18.04.2 amd64 NVIDIA OpenGL/GLX/EGL/GLES GLVND libraries and Vulkan ICD
ii libnvidia-gl-390:i386 390.77-0ubuntu0.18.04.2 i386 NVIDIA OpenGL/GLX/EGL/GLES GLVND libraries and Vulkan ICD
ii libnvidia-ifr1-390:amd64 390.77-0ubuntu0.18.04.2 amd64 NVIDIA OpenGL-based Inband Frame Readback runtime library
ii libnvidia-ifr1-390:i386 390.77-0ubuntu0.18.04.2 i386 NVIDIA OpenGL-based Inband Frame Readback runtime library
ii nvidia-compute-utils-390 390.77-0ubuntu0.18.04.2 amd64 NVIDIA compute utilities
ii nvidia-dkms-390 390.77-0ubuntu0.18.04.2 amd64 NVIDIA DKMS package
ii nvidia-driver-390 390.77-0ubuntu0.18.04.2 amd64 NVIDIA driver metapackage
ii nvidia-kernel-common-390 390.77-0ubuntu0.18.04.2 amd64 Shared files used with the kernel module
ii nvidia-kernel-source-390 390.77-0ubuntu0.18.04.2 amd64 NVIDIA kernel source package
ii nvidia-prime 0.8.8.2 all Tools to enable NVIDIA's Prime
ii nvidia-settings 390.77-0ubuntu0.18.04.1 amd64 Tool for configuring the NVIDIA graphics driver
ii nvidia-utils-390 390.77-0ubuntu0.18.04.2 amd64 NVIDIA driver support binaries
ii xserver-xorg-video-nvidia-390 390.77-0ubuntu0.18.04.2 amd64 NVIDIA binary Xorg driver
其结果dkms status如下：
nvidia, 390.77, 4.18.0-15-generic, x86_64: installed
的内容/var/log/Xorg.0.log显示如下：https://pastebin.com/wBr470Cx
编辑：
进入后/var/log/syslog，我注意到了一些错误输出。首先，打印了以下内容：
Failed to query NVIDIA devices. Please ensure that the NVIDIA device files (/dev/nvidia*) exist, and that user 123 has read and write permissions for those files.
这似乎被报道了这里。为了解决这个问题，我将所有权分配/dev/nvidia*给了nvidia-persistenced组，这有效。那个特定的错误消失了，但以下问题仍然存在：
The daemon no longer has permission to remove its runtime data directory /var/run/nvidia-persistenced
我找到了解决办法这里修复此问题后重新启动，但prime-select nvidia启动卡在“为 UID 121 启动用户管理器”阶段。
目前，我注意到我可以nvidia-settings无问题地运行，但得到以下输出：
ERROR: Error querying enabled displays on GPU 0 (Missing Extension).
ERROR: Error querying enabled displays on GPU 0 (Missing Extension).
** Message: PRIME: No offloading required. Abort
** Message: PRIME: is it supported? no
ERROR: nvidia-settings could not find the registry key file. This file should
have been installed along with this driver at
/usr/share/nvidia/nvidia-application-profiles-key-documentation. The
application profiles will continue to work, but values cannot be
preopulated or validated, and will not be listed in the help text.
Please see the README for possible values and descriptions.
/usr/share/nvidia/nvidia-application-profiles-<version info>-key-documentation我通过复制到修复了注册表文件错误/usr/share/nvidia/nvidia-application-profiles-key-documentation，但Missing Extension错误仍然存在。接下来，我运行sudo apt purge nvidia-*，添加了图形驱动程序 PPA，apt updated 并安装了nvidia-390。现在，使用时唯一的错误nvidia-settings是：
ERROR: Unable to load info from any available system
此时运行nvidia-bug-report.sh不再挂起笔记本电脑，但生成的文件是相同的（水平线上方没有信息）。