Chapter 44. Open Linux Kernel Modules

Introduction

The NVIDIA Linux GPU Driver contains several kernel modules: nvidia.ko, nvidia-modeset.ko, nvidia-uvm.ko, nvidia-drm.ko, and nvidia-peermem.ko.

Two "flavors" of these kernel modules are provided:

Though the kernel modules in the two flavors are different, they are based on the same underlying source code. The two flavors are mutually exclusive: they cannot be used within the kernel at the same time, and they should not be installed on the filesystem at the same time.

The user space components of the NVIDIA Linux GPU driver are identical and behave in the same way, regardless of which flavor of kernel module is used.

Supported Features

The proprietary flavor supports the GPU architectures Maxwell, Pascal, Volta, Turing, and later GPUs.

The open flavor of kernel modules supports Turing and later GPUs. The open kernel modules cannot support GPUs before Turing, because the open kernel modules depend on the GPU System Processor (GSP) first introduced in Turing.

Most features of the Linux GPU driver are supported with the open flavor of kernel modules, including CUDA, Vulkan, OpenGL, OptiX, and X11. We eventually intend for the open kernel modules to replace the proprietary kernel modules.

The following features will only work with the open kernel modules flavor of the driver:

G-sync on notebooks is not yet supported by the open kernel modules.

Use of the open kernel modules on GeForce and Workstation GPUs should be considered Beta quality in this release and no longer requires setting of the "NVreg_OpenRmEnableUnsupportedGpus" nvidia.ko kernel module parameter. The open kernel modules are suitable for broad usage, and NVIDIA requests feedback on any issues encountered that are specific to them.

Known Issues

The following are some known limitations of the open kernel modules versus the proprietary kernel modules with GSP firmware mode disabled:

Installation

Because the two flavors of kernel modules are mutually exclusive, you need to choose which to use at install time. This can be selected with the "--kernel-module-build-directory" .run file option, or its short form "-m". Use "-m=kernel" to install the proprietary flavor of kernel modules (the default). Use "-m=kernel-open" to install the open flavor of kernel modules.

E.g.,

    sh ./NVIDIA-Linux-[...].run -m=kernel-open

As a convenience, the open kernel modules distributed in the .run file are pre-compiled.

Advanced users, who want to instead build the open kernel modules from source, should do the following:

Note that you must use the same version of the .run file and the open kernel module source from https://github.com/NVIDIA/open-gpu-kernel-modules

You can determine which flavor of kernel modules is installed using either `modinfo` or looking at /proc/driver/nvidia/version.

E.g., the proprietary flavor will report:

    # modinfo nvidia | grep license
    license:        NVIDIA

    # cat /proc/driver/nvidia/version
    NVRM version: NVIDIA UNIX x86_64 Kernel Module  [...]

The open flavor will report:

    # modinfo nvidia | grep license
    license:        Dual MIT/GPL

    # cat /proc/driver/nvidia/version
    NVRM version: NVIDIA UNIX Open Kernel Module for x86_64  [...]