If you ever used an Android based device (TV, Smart Watch or Mobile Phone), then you may have come across the term, "Linux Kernel". Android runs on to
If you ever used an Android based device (TV, Smart Watch or Mobile Phone), then you may have come across the term, “Linux Kernel“. Android runs on top of the Linux kernel and all of that device’s input/output, memory management, locks, networking, processes etc. is handled the Linux kernel. For every release of an Android version, that version will use the latest and most stable version of the Linux Kernel as at that release date as there has to be a measure of proven stability and support.
When minor or major bugs are found or security vulnerabilities are patched in the kernel, these fixes need to be reflected onto our android devices also. To make that easier, Linux uses at its base what is called the Long-Term Support (LTS) branch of the kernel. This is a stable version of the kernel which is guaranteed to be maintained for up to two years with fixes for serious bugs and security issues.
Google has traditionally employed a three-step process to deploy these changes:
- System-On-Chip Vendors (Qualcomm, Samsung’s Exynos And MediaTek) adopts the update and customize it to match their chips.
- Original Equipment Manufacturer such as Samsung and LG theme the OS, rebranding Android with new icons, colors, and layouts, often changing core parts of the OS to add extra features and functionality
- Mobile Carrier networks test the new release, certify it for their networks, and deploy it to users via Over the Air Updates.
The problem is that two years of support isn’t enough to incorporate all of these steps. When a major silicon provider such as Qualcomm or MediaTek design a processor, they choose the latest and greatest LTS version of the kernel at some point during the processors design phase. Once that processor is released to OEMs like Samsung or LG, and then the OEM actually makes a device that uses that processor, then up to a year (or maybe even more) has passed since the LTS version was picked by the chip maker. The result is that the actual device can receive less than 1 year’s worth of kernel fixes and then the LTS period ends.
Existing 2 Years Long Term Support (LTS) Is way too short.
To help fix the problem is slow device updates, Android 8.0 Oreo includes Project Treble, a major re-work of Android to make it easier, faster, and less costly for OEMs to update their devices to a new version of Android. But that re-engineering of Android is partly negated by the two year window of LTS kernels.
A the recently concluded Linaro Connect, Project Treble’s lead engineer Iliyan Malchev announced that Greg Kroah-Hartman, the current maintainer of the LTS kernels for the Linux Foundation, has agreed to extend the support period for LTS kernels from 2 years to 6 years. The new Extended LTS (ELTS or XLTS) will start with Linux kernel 4.4.
This is a great change for everybody in the Linux community as it will not only apply to Android but to Linux on the desktop and more importantly to Linux servers. It will be interesting to see what companies like Ubuntu and Red Hat now do with the LTS versions of their distributions.