Two weeks after the launch of the Linux 4.20 kernel series, renowned kernel developer Greg Kroah-Hartman released today the first maintenance update, Linux 4.20.1, marking the new branch as stable and ready for mass deployments.
The Linux 4.20 kernel series was released by Linus Torvalds on December 23rd, 2018, and it is currently the most advanced Linux kernel branch available to date. Linux kernel 4.20.1 is out now to mark the new series as "stable" instead of "mainline" on the kernel.org website, meaning that it's ready for mass adoption by most Linux OS vendors, with Arch Linux being the first.
And it looks like Linux kernel 4.20.1 is a major update to the Linux 4.20 kernel series, changing a total of 187 files, with 1790 insertions and 872 deletions. Therefore, we recommend installing it as soon as it's available in the stable repositories of your favorite GNU/Linux distribution if you're already using Linux kernel 4.20. More details can be found in today's mailinglist announcement.
"I'm announcing the release of the 4.20.1 kernel. All users of the 4.20 kernel series must upgrade. The updated 4.20.y git tree can be found at: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-4.20.y and can be browsed at the normal kernel.org git web browser: http://git.kernel.org/?p=linux/kernel/git/stable/linux-stable.git;a=summary," said Greg Kroah-Hartman.
What's new in Linux kernel 4.20
Since we've missed the launch of the Linux 4.20 kernel series, we'd like to inform our readers about the new features and improvements it includes. Major changes include support for the upcoming AMD Radeon Picasso and AMD Radeon Raven 2 GPUs, along with stable support for AMD Radeon Pro Vega 20 graphics cards and support for Hygon Dhyana x86 CPUs and the C-SKY CPU architecture.
Other enhancements include a new "Early Departure Time" model for the TCP implementation, more performant virtualized graphics thanks to a new mechanism capable of turning memfd regions into dmabufs for QEMU, a couple of optimizations to the lazy TLB mode and PSI for speeding up workloads, as well as numerous new and updated drivers, and the usual round of bug fixes.
Security-related, the Linux 4.20 kernel series adds indirect branch speculation control per task to fix issues with the Single Thread Indirect Branch Predictors (STIBP) and Indirect Branch Prediction Barrier (IBPB) mitigations, better Spectre Variant 2 userspace-userspace protection, and deprecates "minimal retpoline" support for x86 CPUs. For ARM64 (AArch64) CPUs, Linux 4.20 adds a stronger Spectre Variant 4 mitigations.
Those of you interested in running the latest stable kernel on their GNU/Linux distributions can now download Linux kernel 4.20.1 from kernel.org or via our free software portal, that if they want to compile it themselves. Otherwise, watch your distro's stable repositories for the Linux 4.20.x packages in the coming days and update your kernel as soon as possible.