The Linux kernel is complicated. And I’m not even talking about the code.
The code itself is complicated, but you don’t need to bother with it. I’m talking about the release schedule of a Linux kernel.
How often is a
new kernel version released in a year? How long is a kernel supported? There are LTS (Long Term Support) kernels. How long are LTS Linux kernels supported?
The thing is, while these questions may seem simple, the answer is not.
There is no single answer to these questions and it needs some explanations to do so and that is what I am going to do in this article.
Linux kernel release schedule: are there any?
The short answer is that a new kernel version is released every two to three months. The long answer is that it’s not a hard and fast rule.
What it means is that you will often see a new kernel version every two to three months. That’s what the kernel maintainer team is aiming for, but there’s no set deadline for the new version to have to be released exactly 8 weeks after the old version.
A new kernel version is (often) released by Linus Torvalds when it is ready. This usually happens every 2 to 3 months. The version is declared “stable” and is usually numbered in the format of X.Y.
But this is not the end of X.Y’s development. The stable version gets more smaller versions to accommodate bug fixes. These small releases add one more point to the stable kernel to make it like X.Y.Z.
While X.Y is
(often) released by Linux creator Linus Torvalds, the responsibility for keeping the X.Y kernel stable, merging bug fixes, and releasing X.Y.Z versions is handled by
a kernel developer.
How long is
a kernel version supported?
Like the version, there are no fixed dates or calendar for how long a kernel version will be supported.
A regular stable kernel release is usually supported for two and a half to three months, depending on the release of the next stable kernel release.
For example, the stable kernel 5.14 would reach the end of its useful life a couple of weeks after the release of the stable kernel 5.15. The end of support is announced by the maintainer of that particular stable kernel version on the Linux kernel mailing list. Users and contributors are asked to switch to the newly released stable version.
This applies only to normal stable versions of the kernel. There are also LTS (long-term support) kernel versions and they are supported for a much longer period than just 3 months.
The LTS kernel: How long is it supported?
There is also no set release schedule for the LTS kernel. There is usually one LTS kernel release every year, usually the last release of the year and supported for at least two years. But again, there are no set rules here either.
The maintainer of an LTS kernel
may agree to keep a particular LTS kernel for longer than the usual two-year period. The agreement is made according to the need and the actors involved.
This often happens for Android projects. Since two years is not enough for manufacturers to provide support for your hardware and software features, you will often find that some LTS kernels are supported for six years.
You can find this information available on the
Linux kernel website. Your distribution may
not follow regular
Linux kernel versions
If you check the Linux kernel version, your distribution may use an older kernel. It could also be possible that the kernel offered by the distribution has reached the end of its useful life according to the kernel website.
Don’t panic. Its distribution is responsible for patching the kernel for bug fixes and vulnerabilities. Unless you’re really using an obscure Linux distribution, you can rely on your distribution to keep it safe and sound.
You are free to install the latest Linux kernel on Ubuntu or any distribution you use if you have good enough reasons, such as support for newer hardware.
If you want more details, I’ve explained why your distribution uses an outdated Linux kernel here.
No
direct answers
As you can see, there are no direct answers to questions about the Linux kernel release schedule. Everything is tentative.
The good thing, in my opinion, is that if you use a regular Linux distribution, you don’t need to worry much about the release or end-of-life of Linux kernel versions. That’s something handled by its distribution.
I hope you have a slightly better idea about the Linux kernel release cycle or maybe I confused you more than ever. In any case, let me know your views in the comments section.