A Batch Of x86 Speculation Fixes Headed To The Linux 4.19 Kernel

Thomas Gleixner has submitted a batch of x86 fixes today to the Linux 4.19 kernel, which include several changes around the speculative execution vulnerability mitigations.

The x86 speculation fixes for Linux 4.19 include making some checks more robust, a fix for the Foreshadow / L1 Terminal Fault (L1TF) mitigation so it doesn't get disabled on systems utilizing the full physical address space, a fix for the new 32-bit PTI support for Meltdown, and also another fix.

There are also several other more general x86 fixes too around the Kernel Address Sanitizer (KASAN), preventing kernel memory dumps based on user-mode RIP, and other items.

The complete list of changes can be found via this pull request. The pull will presumably be honored ahead of today's expected Linux 4.19-rc2 kernel release.