In this configuration guide, you will learn how to install Mainline Kernel on Linux 9. #centlinux #linux #linuxkernel
Table of Contents
What is Linux Kernel? :
Kernel is the most important component of any Linux operating system. A Linux kernel is works as the interpreter or mediator between computer hardware and software processes.
The Linux Kernel performs following tasks.
- Process Management
- Memory Management
- Device Drivers
- System Calls and Security
Each Linux distribution is shipped with a stable version of Linux Kernel and the supported software and drivers. But the shipped Kernel may not be the the latest one.
The Linux kernel project integrates new code on a rolling basis. Software checked into the project must work and compile without error. Each kernel subsystem is assigned a maintainer who is responsible for reviewing patches against the kernel code standards and keeps a queue of patches that can be submitted to Linus Torvalds within a merge window of several weeks.
Patches are merged by Torvalds into the source code of the prior stable Linux kernel release, creating the -rc release candidate for the next stable kernel. Once the merge window is closed only fixes to the new code in the development release are accepted. The -rc development release of the kernel goes through regression tests and once it is judged to be stable by Torvalds and the kernel subsystem maintainers a new Linux kernel is released and the development process starts all over again.
What is Mainline Linux?:
The Git tree of Linus Torvalds that contains the Linux kernel is referred to as mainline Linux. Every stable kernel release originates from the mainline tree, and is frequently published on kernel.org. Mainline Linux has only solid support for a small subset of the many devices that run Linux. Non-mainline support is provided by independent projects, such as Yocto or Linaro, but in many cases the kernel from the device vendor is needed. Using a vendor kernel likely requires a board support package.
Maintaining a kernel tree outside of mainline Linux has proven to be difficult.
Mainlining refers to the effort of adding support for a device to the mainline kernel, while there was formerly only support in a fork or no support at all. This usually includes adding drivers or device tree files. When this is finished, the feature or security fix is considered mainlined.
Video to install Mainline Kernel on Linux:
Environment Specification:
We are using a minimal Rocky Linux 9 virtual machine with following specifications.
- CPU – 3.4 Ghz (2 cores)
- Memory – 2 GB
- Storage – 20 GB
- Operating System – Rocky Linux release 9.0 (Blue Onyx)
- Hostname – rocky-09.centlinux-com.preview-domain.com
- IP Address – 192.168.116.130/24
Check your Current Linux Kernel:
By using a ssh client, login to your Linux server as root user.
Check your Linux operating system version by executing following command.
# cat /etc/rocky-release Rocky Linux release 9.0 (Blue Onyx)
Check your active Linux Kernel version by using uname command.
# uname -r 5.14.0-70.26.1.el9_0.x86_64
Install ELRepo on Rocky Linux 9:
The latest Linux kernels are distributed through ELRepo yum repository. Therefore, you need to install it before installing Mainline Linux Kernel.
Import the GPG Key of ELRepo repository into the system.
# rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
Install ELRepo on your Linux server by using dnf command.
# dnf install -y https://www.elrepo.org/elrepo-release-9.el9.elrepo.noarch.rpm Last metadata expiration check: 0:38:55 ago on Mon 17 Oct 2022 11:05:16 AM CDT. elrepo-release-9.el9.elrepo.noarch.rpm 8.1 kB/s | 12 kB 00:01 Dependencies resolved. ================================================================================ Package Arch Version Repository Size ================================================================================ Installing: elrepo-release noarch 9.1-1.el9.elrepo @commandline 12 k Transaction Summary ================================================================================ Install 1 Package Total size: 12 k Installed size: 5.0 k Downloading Packages: Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Installing : elrepo-release-9.1-1.el9.elrepo.noarch 1/1 Verifying : elrepo-release-9.1-1.el9.elrepo.noarch 1/1 Installed: elrepo-release-9.1-1.el9.elrepo.noarch Complete!
Build cache for newly installed yum repositories.
# dnf makecache ELRepo.org Community Enterprise Linux Repositor 29 kB/s | 71 kB 00:02 Rocky Linux 9 - BaseOS 952 B/s | 3.6 kB 00:03 Rocky Linux 9 - AppStream 2.0 kB/s | 3.6 kB 00:01 Rocky Linux 9 - Extras 1.2 kB/s | 2.9 kB 00:02 Metadata cache created.
Install Mainline Kernel on Linux:
ELRepo repository contains elrepo-kernel channel that provides the Long Term Supported kernels (kernel-lt) and Main-Line Stable Kernels (kernel-ml) for Red Hat Enterprise Linux based distributions. Both of these Kernel packages are built from the sources available from The Linux Kernel Archives.
Search the elrepo-kernel channel to list down the kernel-ml related packages.
# dnf --disablerepo="*" --enablerepo="elrepo-kernel" list available | grep kernel-ml kernel-ml.x86_64 6.0.2-1.el9.elrepo elrepo-kernel kernel-ml-core.x86_64 6.0.2-1.el9.elrepo elrepo-kernel kernel-ml-devel.x86_64 6.0.2-1.el9.elrepo elrepo-kernel kernel-ml-devel-matched.x86_64 6.0.2-1.el9.elrepo elrepo-kernel kernel-ml-doc.noarch 6.0.2-1.el9.elrepo elrepo-kernel kernel-ml-headers.x86_64 6.0.2-1.el9.elrepo elrepo-kernel kernel-ml-modules.x86_64 6.0.2-1.el9.elrepo elrepo-kernel kernel-ml-modules-extra.x86_64 6.0.2-1.el9.elrepo elrepo-kernel kernel-ml-tools.x86_64 6.0.2-1.el9.elrepo elrepo-kernel kernel-ml-tools-libs.x86_64 6.0.2-1.el9.elrepo elrepo-kernel kernel-ml-tools-libs-devel.x86_64 6.0.2-1.el9.elrepo elrepo-kernel
Install the Mainline Linux Kernel package by using the following command.
# dnf --enablerepo="elrepo-kernel" install -y kernel-ml Last metadata expiration check: 0:00:36 ago on Mon 17 Oct 2022 11:45:44 AM CDT. Dependencies resolved. ================================================================================ Package Arch Version Repository Size ================================================================================ Installing: kernel-ml x86_64 6.0.2-1.el9.elrepo elrepo-kernel 11 k Installing dependencies: kernel-ml-core x86_64 6.0.2-1.el9.elrepo elrepo-kernel 56 M kernel-ml-modules x86_64 6.0.2-1.el9.elrepo elrepo-kernel 51 M Transaction Summary ================================================================================ Install 3 Packages Total download size: 107 M Installed size: 148 M Downloading Packages: (1/3): kernel-ml-6.0.2-1.el9.elrepo.x86_64.rpm 32 kB/s | 11 kB 00:00 (2/3): kernel-ml-modules-6.0.2-1.el9.elrepo.x86 351 kB/s | 51 MB 02:28 (3/3): kernel-ml-core-6.0.2-1.el9.elrepo.x86_64 327 kB/s | 56 MB 02:55 -------------------------------------------------------------------------------- Total 623 kB/s | 107 MB 02:56 Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Installing : kernel-ml-core-6.0.2-1.el9.elrepo.x86_64 1/3 Running scriptlet: kernel-ml-core-6.0.2-1.el9.elrepo.x86_64 1/3 Installing : kernel-ml-modules-6.0.2-1.el9.elrepo.x86_64 2/3 Running scriptlet: kernel-ml-modules-6.0.2-1.el9.elrepo.x86_64 2/3 Installing : kernel-ml-6.0.2-1.el9.elrepo.x86_64 3/3 Running scriptlet: kernel-ml-core-6.0.2-1.el9.elrepo.x86_64 3/3 Running scriptlet: kernel-ml-6.0.2-1.el9.elrepo.x86_64 3/3 Verifying : kernel-ml-6.0.2-1.el9.elrepo.x86_64 1/3 Verifying : kernel-ml-core-6.0.2-1.el9.elrepo.x86_64 2/3 Verifying : kernel-ml-modules-6.0.2-1.el9.elrepo.x86_64 3/3 Installed: kernel-ml-6.0.2-1.el9.elrepo.x86_64 kernel-ml-core-6.0.2-1.el9.elrepo.x86_64 kernel-ml-modules-6.0.2-1.el9.elrepo.x86_64 Complete!
Mainline Linux Kernel 6.0 has been installed on your Rocky Linux server.
To load the new Linux kernel, you need to restart your Linux machine.
# reboot
After reboot, you will see that, the newly installed Linux Kernel 6.0 has been added to the GRUB boot menu.
Start your Linux operating system with newly installed Kernel 6.0.
After startup, execute the following command at Linux CLI to check your active Kernel version.
# uname -r 6.0.2-1.el9.elrepo.x86_64
Uninstall Mainline Linux Kernel 6.0:
Uninstall process of Linux Kernel 6.0 is very straight forward, But we have included it in this configuration guide for the sake of completeness.
Restart your Linux operating system.
# reboot
Start the Linux operating system with an older version of Linux Kernel.
After successful startup, check the active kernel version by executing the following command at Linux CLI.
# uname -r 5.14.0-70.26.1.el9_0.x86_64
Your Linux operating system is now using an older version of Linux Kernel.
Linux Kernel 6.0 is not your active kernel, therefore you can safely uninstall it by using dnf command.
# dnf remove -y kernel-ml Dependencies resolved. ================================================================================ Package Arch Version Repository Size ================================================================================ Removing: kernel-ml x86_64 6.0.2-1.el9.elrepo @elrepo-kernel 0 Removing unused dependencies: kernel-ml-core x86_64 6.0.2-1.el9.elrepo @elrepo-kernel 98 M kernel-ml-modules x86_64 6.0.2-1.el9.elrepo @elrepo-kernel 50 M Transaction Summary ================================================================================ Remove 3 Packages Freed space: 148 M Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Erasing : kernel-ml-6.0.2-1.el9.elrepo.x86_64 1/3 Erasing : kernel-ml-modules-6.0.2-1.el9.elrepo.x86_64 2/3 Running scriptlet: kernel-ml-modules-6.0.2-1.el9.elrepo.x86_64 2/3 Running scriptlet: kernel-ml-core-6.0.2-1.el9.elrepo.x86_64 3/3 Erasing : kernel-ml-core-6.0.2-1.el9.elrepo.x86_64 3/3 Running scriptlet: kernel-ml-core-6.0.2-1.el9.elrepo.x86_64 3/3 Verifying : kernel-ml-6.0.2-1.el9.elrepo.x86_64 1/3 Verifying : kernel-ml-core-6.0.2-1.el9.elrepo.x86_64 2/3 Verifying : kernel-ml-modules-6.0.2-1.el9.elrepo.x86_64 3/3 Removed: kernel-ml-6.0.2-1.el9.elrepo.x86_64 kernel-ml-core-6.0.2-1.el9.elrepo.x86_64 kernel-ml-modules-6.0.2-1.el9.elrepo.x86_64 Complete!
Restart your Linux server again.
# reboot
You can see that Mainline Linux Kernel 6.0 has been removed from your operating system.
Conclusion – Install Mainline Kernel on Linux 9:
In this configuration guide, you have learned how to install Mainline Kernel on Linux 9. We recommend that for learning more about Linux Kernel, you should read How Linux Works, 2nd Edition: What Every Superuser Should Know Second Edition (PAID LINK) by Brian Ward.
