How To Install Kernel 6.9.9 On Ubuntu, Debian And Derivative Systems

The Linux kernel is the core component of any Linux operating system, managing hardware resources and system processes.

In this guide we will be installing Kernel 6.9.9, which has been released a while go, coming with changes.

Kernel 6.9.9 highlights:

• libbpf Update: Fixed an issue in the libbpf library to prevent the unintended closing of file descriptors, enhancing stability in BPF applications.
• null_blk Driver Adjustment: Added a check in the null_blk driver to prevent configurations where the zone capacity is smaller than the zone size, aligning with real device setups.
• Dell G15 5511 Fan Control: Included the Dell G15 5511 model in the fan control whitelist, allowing users to manage fan settings effectively on this hardware.
• AMD GPU Driver Fix: Addressed a UBSAN warning in the AMD GPU driver by adjusting a variable-sized array, improving system stability.
• ALSA UMP Protocol Default: Set a default protocol in the ALSA UMP driver when not specified explicitly, preventing undefined behavior in MIDI devices.
• Cadence SPI Driver Enhancement: Ensured data lines are set to low during the dummy-cycle period in the Cadence SPI driver, preventing unintended mode byte transmissions.

In this guide we will be installing Kernel 6.9.9, which has been released a while go, bringing some fixes and enhancements only.

Check your current kernel version:

Before proceeding with the installation, verify your current kernel version by running:

uname -r

How to install Kernel 6.9.9 on Ubuntu, Linux Mint, Debian, and derivative systems (amd64/x86_64):

Step 1: Update Your System

Run the following commands to ensure your system is up to date:

sudo apt update && sudo apt upgrade -y

This will update your package list and upgrade all installed packages to their latest versions.

• What Does apt update Do?
  This command updates the package list to reflect the latest versions available from your repositories.
• What Does apt upgrade Do?
  It upgrades all the packages that have new versions available while keeping existing dependencies intact.

Step 2: Download the Kernel 6.9.9 Packages

Download the necessary kernel packages from the official Ubuntu repositories or the kernel website:

wget -c https://kernel.ubuntu.com/mainline/v6.9.9/amd64/linux-headers-6.9.9-060909-generic_6.9.9-060909.202501290741_amd64.deb
wget -c https://kernel.ubuntu.com/mainline/v6.9.9/amd64/linux-headers-6.9.9-060909_6.9.9-060909.202501290741_all.deb
wget -c https://kernel.ubuntu.com/mainline/v6.9.9/amd64/linux-image-unsigned-6.9.9-060909-generic_6.9.9-060909.202501290741_amd64.deb
wget -c https://kernel.ubuntu.com/mainline/v6.9.9/amd64/linux-modules-6.9.9-060909-generic_6.9.9-060909.202501290741_amd64.deb

Step 3: Install the New Kernel

Install the downloaded packages using dpkg:

sudo dpkg -i linux-headers-6.9*.deb linux-modules-6.9*.deb linux-image-6.9*.deb

Step 4: Update GRUB and Reboot

Once the kernel installation is complete, update GRUB to ensure the new kernel is recognized:

Regenerate the GRUB Configuration

Run the following command to update GRUB with the latest installed kernel:

sudo update-grub

Verify GRUB Configuration

To confirm that the new kernel has been detected, check the GRUB configuration:

cat /boot/grub/grub.cfg | grep 'menuentry'

This should list all available kernels, including Kernel 6.9.9.

Reboot the System

Restart your computer to apply the changes:

sudo reboot

• Select the New Kernel (if needed) – If the system doesn’t automatically boot into the new kernel, you can manually select it:
  • Hold Shift or Esc during boot to access the GRUB menu.
  • Navigate to Advanced options for Ubuntu.
  • Choose the entry with Kernel 6.9.9.
  • Press Enter to boot.

Verifying the Installed Kernel

After rebooting, confirm the new kernel version:

uname -r

Rolling Back to a Previous Kernel

If you encounter issues with the new kernel, you can revert to an older version:

• Reboot and Access the GRUB Menu -Restart your system and hold Shift or Esc to enter the GRUB boot menu.
• Select Advanced options for Ubuntu – Choose an older kernel version and boot into it.
• Remove Kernel 6.9.9 (if desired) – If you prefer to remove the new kernel permanently, run:

sudo apt remove linux-headers-6.9* linux-modules-6.9* linux-image-6.9*
sudo update-grub
sudo reboot

Conclusion

Linux Kernel 6.9.9 is a maintenance release that focuses on stability improvements and bug fixes across multiple subsystems. Key updates include enhancements to libbpf, preventing unintended file descriptor closures, and adjustments to the null_blk driver, ensuring proper zone configurations.

Hardware compatibility has also been improved with the inclusion of the Dell G15 5511 model in the fan control whitelist, allowing better thermal management. Additionally, fixes in the AMD GPU driver and ALSA UMP protocol handling contribute to a more stable user experience for graphics and MIDI audio users.

For embedded systems and specialized hardware, updates like the Cadence SPI driver enhancement improve reliability in data transmission. These refinements, while not introducing new features, play a crucial role in maintaining a stable and efficient Linux ecosystem.

Users experiencing issues with BPF applications, AMD GPUs, MIDI devices, or Dell fan control should consider upgrading to Linux 6.9.9 to benefit from these essential fixes and improvements.

Newer Kernel 6.9.x versions are also available:

How To Install Kernel 6.9.10 On Ubuntu, Debian And Derivative Systems