Linux Kernel 5.3 adds 16 million of new IPv4 addresses and more

02.10.2019 2,745 16

Martin Deshev

Linux Kernel 5.3 has been around for a couple of weeks now and the first impressions are now in. The new release includes quite a few new features and adds support for more hardware. There are also some important additions that will be of use to many admins.

While most of the features are desktop-centric, there are some that will also benefit enterprise servers. One of them is the new IPv4 patch.

It allows 0.0.0.0/8 as a valid IP address range. This means that around 16 million new IPv4 addresses can now be used with the system. This is definitely a big and important improvement for cloud service providers and businesses which use containers at scale.

It’s great news considering that many companies and even service sites still use IPv4 and are yet to even implement IPv6. This will be a breath of air, but it doesn’t mean companies should neglect IPv6. Instead they should use the extra time to implement it better.

Another cloud-focused improvement is the changes to RISC-V and the support for x86 Zhaoxin processors. RISC-V gets Image header support, high-resolution timers and dynamic ticks. It also adds Huge-pages, splits into two stages the initial page table and adds support for CONFIG-SCO. There’s also a feature to avoid reserving memory between RAM start and the kernel setup_bootmem().

Among the list of changes we see several file system improvements. One of the changes is the faster lookups for case-insensitive EXT4. You’d say that this was introduced in Kernel 5.2 and you’d be right. However, now the feature has been reworked and the true performance improvements are coming. There are also new BULKSTAT and INUMBERS ioctls in XFS. Moreover, you can enjoy the use of native F2FS swap file support.

Hardware gets some love, too

Apart from the x86 Zhaoxin support, Kernel 5.3 also adds some other new improvements in the hardware department. Among them is support for AMD NAVI graphics cards, for example the Radeon RX 5700 series. It also supports Intel HDR display.

Kernel 5.2 now also supports the new ARM SoCs and boards like the Nvidia Jetson Nano. It introduces support for Intel Speed Select and Nvidia Turing TU116.

Fans of IoT will also have some new stuff to play around with. Kernel 5.3 adds support for the ACRN small footprint hypervisor. It includes real-time capabilities for multiple guest operating systems.

If you’re especially playful, there’s now support for MacBook and MacBook Pro keyboards. There are new drivers for Chrome OS for custom Chromebook hardware. Other new hardware features: Saitek R440 Force Wheel, Ugee Rainbow CV720, Wacom MobileStudio Pro, and Wacom 2nd-gen Intuos Pro Small graphics tablets, and the Logitech MX3000 receiver.

That’s the quick gist of the new stuff in Kernel 5.3. There is a whole lot of other smaller changes and improvements all over the system. The release notes are detailed by Linus Torvalds himself.