Posted last month were Linux patches for removing support for very old i486 and early i586 CPUs. While not yet mainlined to the Linux kernel contrary to some of the reporting elsewhere, this work for removing TSC-less and CX8-less x86 CPUs remains ongoing and out today is the second iteration of the patches.
The code aims to get rid of various “complicated” emulation facilities used for handling “ancient” 32-bit CPUs that is very seldom used by anyone on a modern Linux kernel. In turn maintaining this old x86 CPU support is a maintenance burden and could free up developer resources to focus on more meaningful hardware support and facilitate easier kernel improvements without the old cruft.
Sent out today was the second iteration of the patches that is now re-based against the latest upstream Linux Git codebase and fixing a variety of smaller code issues that were raised during the original round of code review.
Those interested can find these v2 patches via the Linux kernel mailing list. We’ll see if this clean-up patch series is deemed ready in time for the upcoming Linux 6.16 merge window or if it will be held off another cycle or longer before seeing the very old x86 CPU support gutted. Removing this old support lightens the Linux x86 code by more than 14k lines of code.