Why Linux 4.20 Is End‑of‑Life and How to Upgrade to the 5.0 Kernel

Linux kernel 4.20.17 is the last point release of the 4.20 series. Maintainer Greg Kroah‑Hartman announced the series' end‑of‑life and strongly recommends that all users upgrade to a newer kernel series as soon as possible.

The 4.20 series was originally released on 23 December 2018 and introduced several improvements, including indirect branch speculation control per task and fixes for Spectre‑related issues such as indirect branch prediction barrier (IBPB) and single‑thread indirect branch predictor (STIBP) mitigations.

Additional enhancements in 4.20 include a more effective Spectre Variant 2 user‑space protection mechanism, stronger Spectre Variant 4 mitigations for ARM64 (AArch64) CPUs, and expanded hardware support for AMD Radeon Pro Vega 20 GPU, C‑SKY CPUs, Hygon Dhyana x86 CPUs, as well as AMD Radeon Picasso and Raven 2 GPUs.

"I announce the release of 4.20.17. This is the final 4.20.y kernel. It is now end‑of‑life; please upgrade to the 5.0.y kernel tree. All 4.20 users must upgrade," Greg Kroah‑Hartman wrote on the mailing list.

For users running a GNU/Linux distribution with a 4.20 kernel, there are two options: update to the latest 4.20.17 point release or migrate to the 5.0 kernel series. If the distribution does not yet provide a 5.0 kernel, users should consider moving to a supported long‑term support (LTS) kernel.

Supported LTS kernels include Linux 4.19 (recommended), 4.14, 4.9, 4.4, and 3.16. Advanced users can also download and compile the latest 5.0 kernel directly from kernel.org, provided they understand the build process.