Linux's KVM Preps For APX Support In VMs
Among the Kernel-based Virtual Machine (KVM) work being queued ahead of the upcoming Linux 7.2 merge window are preparations for supporting Advanced Performance Extensions within KVM virtual machines.
Advanced Performance Extensions is a major update to x86 for future Intel/AMD CPUs. APX doubles the number of general purpose registers, there is a new direct jump instruction, optimized state save/restore, and other ISA improvements. Intel Nova Lake and Xeon Diamond Rapids processors will be debuting APX later it will also come to AMD CPUs.
For Linux 7.2 it doesn't look like the actual KVM APX support will be ready but a lot of preparations being made so hopefully it will be ready for v7.3, which still puts it ahead of Diamond Rapids and Nova Lake processors shipping.
Merged to KVM's "next" Git branch recently was the preparation code for KVM APX, including to ready KVM for going from 16 to 32 general purpose registers. There was also another follow-up merge to also prepare for the upcoming APX support.
So it's not over the finish line yet but with Linux 7.2 the initial preparations are being made to prepare KVM for supporting APX within VMs.
Advanced Performance Extensions is a major update to x86 for future Intel/AMD CPUs. APX doubles the number of general purpose registers, there is a new direct jump instruction, optimized state save/restore, and other ISA improvements. Intel Nova Lake and Xeon Diamond Rapids processors will be debuting APX later it will also come to AMD CPUs.
For Linux 7.2 it doesn't look like the actual KVM APX support will be ready but a lot of preparations being made so hopefully it will be ready for v7.3, which still puts it ahead of Diamond Rapids and Nova Lake processors shipping.
Merged to KVM's "next" Git branch recently was the preparation code for KVM APX, including to ready KVM for going from 16 to 32 general purpose registers. There was also another follow-up merge to also prepare for the upcoming APX support.
So it's not over the finish line yet but with Linux 7.2 the initial preparations are being made to prepare KVM for supporting APX within VMs.