Released on August 12, 2018, by Linus Torvalds, the Linux 4.18 kernel series introduced Spectre Variant 1 and Spectre Variant 2 mitigations for 32-bit ARM architectures, Spectre Variant 4 mitigations for the ARM64 (AArch64) and ARMv8 architectures, and initial support for the Radeon Vega 20 GPUs. Because Linux kernel 4.18 isn’t a long-term supported (LTS) series, it reached end of life with the Linux 4.18.20 update released last week by Greg Kroah-Hartman, on November 21, 2018. Therefore, all users using the Linux 4.18 kernel series are now urged to upgrade to the latest branch, namely Linux kernel 4.19.