Android is built on top of the Linux kernel, which means the OEMs are obliged to provide the source code, upon request, of any Linux kernel binaries they distribute on devices they sell. Most vendors nowadays release the sources within a short period of their devices hitting the market, fulfilling their legal obligation of the General Public License v2. Companies like Samsung, Sony, and Xiaomi maintain a particularly good track record of releasing these sources and we now have another example of their commitment towards the aftermarket development community. The kernel sources for the recently released Samsung Galaxy S21 series and the Redmi Note 9T are now available for download. Sony, on the other hand, has released the kernel sources corresponding to the Xperia 1 II's Android 11 release.

Samsung Galaxy S21

You can now head over to the Samsung Open Source Release Center website and access the kernel source code for the Exynos/Snapdragon Galaxy S21 (SM-G991B/SM-G991U), S21 Plus (SM-G996B/SM-G996U), and S21 Ultra (SM-G998B/SM-G998U). For those of you who have already managed to purchase one of these smartphones or plan on getting one, the kernel source code release means that you'll soon see third-party development for Samsung's latest flagship lineup pick up the pace on our forums.

Samsung Galaxy S21 Kernel Sources

Galaxy S21 Forums ||| Galaxy S21 Plus Forums ||| Galaxy S21 Ultra Forums

Redmi Note 9T

Xiaomi announced the Redmi Note 9T just a couple of weeks ago as the global variant of the China-exclusive Redmi Note 9 5G (code-name "cannon"). Readers come to our forums realizing the massive development potential of this great mid-ranger 5G phone, and for that, they require access to the kernel source code. To the rejoicing of these readers, Xiaomi has released the kernel source code for the Linux kernel binaries that ship with the Redmi Note 9T's Android 10 firmware.

Redmi Note 9T/Redmi Note 9 5G Kernel Sources

Redmi Note 9T Forums

Sony Xperia 1 II

Sony originally released the kernel source code for the Xperia 1 II back in June 2020. That was for the initial Android 10 release, which the device was shipped with. Last month, the company rolled out the Android 11 update for the Xperia 1 II. However, the source code for the same wasn't made available up until now. Visit Sony's Developer World page from the link below to inspect or download the code.

Sony Xperia 1 II Android 11 Kernel Sources

Sony Xperia 1 II Forums

With kernel source code availability, the modding community can come up with custom kernel builds and add new capabilities to the devices that are otherwise not offered in the stock configuration. Such source releases also help developers to port the popular TWRP custom recovery as well as custom ROMs (e.g. LineageOS) for the device which, in turn, benefit users who aren’t satisfied with the stock ROM.