Warning: new nvidia drivers in Fedora

If you have followed my instructions on setting up a system to use Nvidia drivers, things have worked pretty good until now.

This week I noticed that xorg-x11-drv-nvidia-384.90-1 has been pushed out from the rpmfusion non-free repo. (The previous driver was 384.59-2.) At first glance, you might not think too much about it. Its a small number bump.

If you reboot your system and you find that you no longer have a high resolution desktop or Cinnamon says its running in software emulation mode instead of hardware accelerated mode...then you have a problem.

To fix it, run the following command as root:

grubby --remove-args="nomodeset nvidia-drm.modeset=1" --update-kernel=ALL

The new driver is aimed at some work going on for Fedora 27 wayland support. It does not like mode setting and it does not like the way GDM does things. So, you have to get rid of it from all menu items by using the above command.

The next thing you may notice is that your AI programs don't run anymore. This is because we now have a CUDA driver mismatch. In the cuda8-samples package that is distributed as part of the CUDA 8 developer's toolkit, (which I also have you to compile when setting up a CUDA environment) you will find a utility called, deviceQuery. Run this and you will see something like this:

deviceQuery, CUDA Driver = CUDART, CUDA Driver Version = 9.0, CUDA Runtime Version = 8.0, NumDevs = 1, Device0 = GeForce GTX 1050 Ti

As you can see, we have CUDA 9 drivers now and a CUDA 8 runtime. That means we need to update our CUDA runtime environment to version 9 and recompile our AI programs to the new API.

For now, just know that this issue exists. If you are adventurous, go ahead and convert. (CUDA 9 has lots of new stuff.) I'll write about how to do the update in a future blog.

Another alternative is to not allow the xorg-x11-drv-nvidia update for now. With Fedora 27 just around the corner, we're all going to have to update to CUDA 9 anyways. But you can delay until you're ready to upgrade.