Two notable AMD CPU feature additions were merged overnight for the in-development Linux 6.17 kernel.
First and most prominently: AMD’s Hardware Feedback Interface driver has been merged! This new driver has been in development the past year for Linux and is designed to provide better classification and dynamic rankings around heterogeneous core processors for the AMD Ryzen parts with a mix of full-fat/classic and “dense” cores, such as various Ryzen AI 300 series models with a mix of Zen 5 and Zen 5C cores.
AMD HFI provides guidance to the kernel/OS for better performance and energy efficiency abilities on each CPU core for more optimal task scheduling and resource allocation. I haven’t yet run benchmarks myself on the AMD Hardware Feedback Interface for performance and power impact but it’s on my TODO list now that the driver is finally in the mainline kernel.
The AMD Hardware Feedback Interface driver was mainlined as part of the x86/platform updates for Linux 6.17. This new documentation file outlines the AMD HFI driver and capabilities under Linux.
The second AMD feature merged overnight for Linux 6.17 is the CPUID faulting support. While CPUID faulting support has been long supported by Intel CPUs and under Linux, it’s finally here for AMD processors. Only recently did AMD post patches for user CPUID faulting as a feature beneficial for tthe likes of VMMs/hypervisors for trapping user-space CPUID instructions.
The AMD CPUID faulting support landed with the x86/cpu pull for the v6.17 merge window.
Not limited to just AMD processors but another Linux 6.17 pull worth mentioning is the x86/boot updates. Notable with the x86/boot code is UEFI SBAT for Secure Boot Advanced Targeting as a Secure Boot image revocation facility.
