3.18 is on EOL(End of Life).
For quite sometime now (nearly a year), Linux kernel 3.18 is on EOL(End of Life) status , meaning critical bug fixes from Linux mainline won’t be back ported to 3.18 in the near future.
Now there is a something called Sony’s Open Devices Program. Apart from providing AOSP device configurations on GitHub, they also aim of running recent kernel versions on their supported Open devices.
Result? Welcome 4.4 kernel for z2_plus/z2_row.
Kernel 4.4 is a Super long-term supported kernel and the CIP community plans to maintain 4.4 for security and bug fixes for more than 10 years. Kernel 4.4 brings improvements ranging from memory management, better scheduling, security, performance improvements and much more compared to 3.18
- With kernel 4.4, the device gets an improved, effective implementation of EAS. Currently the kernel has commits up-to EAS r1.4, same as kernel_common/android-4.4
- Kernel 4.4 also brings better compatibility with Clang. Which is the recommended tool-chain for newer Linux kernels.
A newer version of a kernel for a device rarely happens and is a big deal as it comes with much newer drivers, security improvements, and longevity.
It is a shame though that there is barely any spotlight highlighting the efforts put up by such talented developers.
- @MR.HACKER5476 for initial z2_plus pie bringup
- @faizauthar12 for initial 3.18 kernel bringup
- @nathanchance for android-linux-stable, android-kernel-clang
- @joshuous and @RenderBroken for EAS-Project
- ZukCustomGoodies members for testing and bug reporting
ROMs supporting 4.4 as of right now.