There are so many tutorials teaching how to install the latest Kernel, while, this one is going to show you how to downgrade to the original GA (General Availability) Kernel 5.15 in Ubuntu 22.04.

The GA Kernel is shipped by default in the first stable release of Ubuntu 22.04. By rolling out Ubuntu 22.04.1, 22.04.2, and 22.04.3, it now has Kernel 6.2 as default (next should be 6.5 in 22.04.4).

Don’t know why, but someone asked how to revert back the original Kernel 5.15. So, here’s the quick tips show you how.

Install GA Kernel in Ubuntu:

All current Ubuntu releases, including the next Ubuntu 24.04 Noble, include linux-image-generic package in system repositories for the Generic Linux kernel.

Simply press Ctrl+Alt+T on keyboard to open terminal. Then, run command to install it:

sudo apt install linux-image-generic

Run sudo apt update if the command above does not work.

Boot Your Ubuntu with Kernel 5.15

After installing the kernel package, you have to either set it as default in boot-menu or remove the HWE 6.2 Kernel.

Firstly, boot/reboot your machine, press Esc while booting to show the Grub menu. Then, select boot the Kernel 5.15 from “Advanced options for Ubuntu” -> “Ubuntu, with Linux 5.15.0-xx-generic”.

After booted into Ubuntu and logged in, verify by running command in terminal window (Ctrl+Alt+T):

uname -a

To make it default, either remove the HWE kernel by running command:

sudo apt remove --autoremove linux-image-generic-hwe-22.04

Or, use Grub Customizer to set default boot entry under ‘General settings’ tab. See how to install Grub Customizer in Ubuntu.

For those who want to install the most recent Kernel 6.6 with new hardware support or compatibility fixes, it’s now available in the zabbly repository for Ubuntu 20.04, Ubuntu 22.04, and Debian 12.

Linux 6.6 was released few weeks ago as the latest Kernel series. It features PSR power saving for Intel 4th/5th CPU, initial PECI support for 4th Gen Xeon, initial support for the Intel Lunar Lake VPU4, Dynamic Boost Control support for AMD Ryzen laptops, as well as various new hardware support. See HERE for more.

As Ubuntu Mainline Kernel PPA is stuck at old RC5 for unknown reason, there’s NO official package for the new Kernel release.

For choice, the Zabbly repository maintained by Ubuntu core developer (quit a few months ago) has updated the new kernel package for Ubuntu 22.04 & 20.04.

Add Zabbly Repository & install latest Kernel

Press Ctrl+Alt+T on keyboard to open terminal. Then, run the commands below one by one to add the repository and install latest Kernel:

• Download & install the key:

  sudo wget -O - https://pkgs.zabbly.com/key.asc |sudo tee /etc/apt/keyrings/zabbly.asc

• Setup the repository via single command:

  sh -c 'cat <<EOF > /etc/apt/sources.list.d/zabbly-kernel-stable.sources
  Enabled: yes
  Types: deb
  URIs: https://pkgs.zabbly.com/kernel/stable
  Suites: $(. /etc/os-release && echo ${VERSION_CODENAME})
  Components: main
  Architectures: $(dpkg --print-architecture)
  Signed-By: /etc/apt/keyrings/zabbly.asc
  
  EOF'

  This is a single command for Ubuntu/Debian. For their based systems, you have to replace $(. /etc/os-release && echo ${VERSION_CODENAME}) with jammy (for 22.04 base), focal (for 20.04 base), or bookworm for Debian 12 base.

• Finally, update & install the new kernel:

  sudo apt update

  sudo apt install linux-zabbly

  

In case the previous steps are not clear enough, or it broke things up, see this step by step detailed guide instead.

Want to install the latest Linux Kernel 6.5? It’s there in your Ubuntu 22.04 system repository!

Linux Kernel 6.5 was released a week ago with exciting new features, including initial USB4 v2, MIDI 2.0 support, much faster parallel direct I/O overwrite on EXT4, Acer Aspire 1 Arm laptop, Sony Xperia M4 Aqua phone, open-source driver support for Lenovo ThinkPad X13s laptop, enhanced load balancing for Intel hybrid CPUs, Intel SoundWire ACE2.x support, and more.

Ubuntu built the Kernel package in the Mainline PPA, which sadly only installs in Ubuntu 23.10 so far due to dependency issue.

Now, for Ubuntu 22.04 LTS, Linux 6.5 has been made into the main repository as OEM Kernel!

What is OEM Kernel

Ubuntu LTS has a few different Kernel series. They include GA Kernel that is default in first stable release, HWE Kernel (6.2 at the moment) backported from newer Ubuntu short-term releases and default in point release (e.g., Ubuntu 22.04.1, 22.04.2).

The OEM Kernel is an Ubuntu derivative kernel, specifically for use in OEM projects.

It is a staging Kernel series with shorter life cycle. It will get rolled off to the next HWE kernel once all the fixes have been forward-ported. Meaning, Linux 6.5 will probably be the default in next Ubuntu 22.04.4.

The OEM Kernel is made and officially supported by Ubuntu Team. It’s SAFE to run in any machine according to the Wiki page.

How to Install OEM Kernel 6.5 in Ubuntu 22.04

To install the Kernel package, simply press Ctrl+Alt+T on keyboard to open a terminal window.

When terminal opens, run command to refresh package cache:

sudo apt update

Finally, install the kernel package via:

sudo apt install linux-oem-22.04d

When done. Restart your computer, and verify by running command in a terminal window:

uname -a

Uninstall OEM Kernel 6.5

To restore the old Kernel, first start/restart your machine and choose the previous Kernel (under “Advanced”) in boot menu.

In case you removed the old Kernels, install it back by running command:

sudo apt install --install-recommends linux-generic-hwe-22.04

Once you system is boot up with an old Kernel, open terminal and run command to remove OEM Kernel 6.5:

sudo apt remove --autoremove linux-oem-22.04d linux-headers-6.5.0-*-oem linux-image-6.5.0-*-oem linux-modules-6.5.0-*-oem

Linus Torvalds announced the release of Kernel 6.5 this Sunday. He wrote:

So nothing particularly odd or scary happened this last week, so thereis no excuse to delay the 6.5 release.

I still have this nagging feeling that a lot of people are on vacation and that things have been quiet partly due to that. But this release has been going smoothly, so that’s probably just me being paranoid. The biggest patches this last week were literally just to our selftests.

Linux Kernel 6.5 features enhanced load balancing for Intel hybrid CPUs, Intel SoundWire ACE2.x support, and new meteor Lake-S driver.

For AMD, it now uses AMD P-State driver by default rather than CPUFreq for Zen 2 and newer systems, and support Error Detection And Correction (EDAC) subsystem for AMD Ryzen 7000 series.

The AMDGPU driver enabled FreeSync video mode by default, got performance improvements and power saving optimizations.

The release also improved LoongArch support with Simultaneous Multi-Threading, SIMD/Vector Extensions. Added support for the Alibaba T-Head TH1520 RISC-V 64-bit processor, and IBM POWER10 received DEXCR support.

Other changes in Kernel 6.5 include:

• Mainline support for the Acer Aspire 1 Arm laptop, Sony Xperia M4 Aqua phone.
• Enable new Permission Indirection Extensions for Armv8.9
• Open-source driver support for Adreno 690 that found in Lenovo ThinkPad X13s laptop.
• Mediatek Vcodec driver has added support for AV1 and HEVC/H.265 stateless video codecs.
• Much faster parallel direct I/O overwrite on EXT4.
• Microsoft Xbox controller rumble support
• Initial support for USB4 v2.
• MIDI 2.0 support

How to Install Linux Kernel 6.5 in Ubuntu

As usual, the mainline Kernel PPA build the packages available to download at the link below:

Sadly, this build only installs in Ubuntu 23.10 due to dependency updates. For modern 64-bit (x86_64) PC/laptop, select download the amd64 build packages:

1. linux-headers-6.5.0-060500-xxxxxx_all.deb
2. linux-headers-6.5.0-060500-generic_xxx_amd64.deb
3. linux-modules-6.5.0-060500-generic_xxx_amd64.deb
4. linux-image-unsigned-6.5.0-060500-generic_xxx_amd64.deb

After downloading them, right click on blank area in Downloads page and select “Open in Terminal”. Finally, install the kernel packages via command:

sudo apt install ./linux*.deb

For Ubuntu 22.04, Kernel 6.5 is available to install by running sudo apt install linux-oem-22.04d command in terminal.

Ubuntu 20.04 user can install it through the new zabbly repository.