KB 933073 - Using dmesg and Kernel Module Checks to Troubleshoot NVIDIA GPU Issues

KB 933073 - Using dmesg and Kernel Module Checks to Troubleshoot NVIDIA GPU Issues

 Overview

This article outlines how to use dmesg logs and kernel module commands to diagnose issues where the operating system fails to detect NVIDIA GPUs—even though they appear in the system's BMC (Baseboard Management Controller).
When to Use This
You may need this guide if:
  • nvidia-smi reports: NVRM: No NVIDIA GPU found

  • GPUs are visible in BMC or IPMI but not in the OS

  • You're seeing driver or hardware initialization errors during boot

Step 1: Check Kernel Ring Buffer (dmesg) for Errors

The dmesg command shows messages from the kernel that are helpful for low-level diagnostics.
  1. sudo dmesg | grep -iE "nvidia|gpu|pci|acpi|firmware" | grep -iE "fail|error|not found|disable"
What to Look For:
  • module verification failed — Indicates Secure Boot is blocking the NVIDIA kernel module.

  • No NVIDIA GPU found — The NVIDIA driver was loaded but no GPUs were detected on the PCI bus.

  • firmware: failed to load — A required firmware blob was missing.

  • ACPI: device not enabled — BIOS/UEFI settings may have disabled PCIe devices.

Step 2: Check if the NVIDIA Kernel Module is Loaded

Linux uses kernel modules (drivers) to interface with hardware like NVIDIA GPUs.

  1. lsmod | grep nvidia

If you get output like:

  1. nvidia_uvm           860160  0
  2. nvidia_drm            57344  2
  3. nvidia_modeset       1114112  4 nvidia_drm
nvidia              
  4. nvidia              23474176  260 nvidia_uvm,nvidia_modeset

→ The driver is loaded and likely functioning.

If there is no output:

The module didn’t load. Check dmesg again or try loading it manually:

  1. sudo modprobe nvidia

Step 3: Check for Secure Boot Blocking the Driver

Secure Boot can prevent unsigned kernel modules like NVIDIA’s from loading.
  1. mokutil --sb

  • SecureBoot enabled → You'll see SecureBoot enabled

  • Disable it from the BIOS or sign the NVIDIA module with MOK (Machine Owner Key).

Step 4: Check PCI Bus for NVIDIA Devices

This helps confirm whether the GPU is physically present and detected at the PCIe level.
  1. lspci | grep -i nvidia

If no output appears, the GPU is not even seen by the PCIe bus. Potential causes:

  • Hardware issue

  • GPU seated improperly

  • PCIe slot/bifurcation misconfigured in BIOS

  • Faulty riser or cable

Check if nvidia kernel module is available:
  1. modinfo nvidia

If modinfo says "module not found", the driver installation might be corrupted or incomplete.