Linux Kernel: KVM Virtualization Fixes and Live Update Patches
Linus Torvalds merged significant KVM fixes addressing ARM64 erratum workarounds and x86 virtualization issues, including a new module parameter to disable problematic CET virtualization. Additional fixes for the live update subsystem address kexec handover and memory file descriptor preservation.
Duration: PT1M51S
Transcript
Good morning, this is your Linux Kernel briefing for May 14th, 2026.
Today's activity focused on critical virtualization fixes with three commits addressing KVM and live update functionality.
Linus Torvalds merged a substantial KVM fix collection from Paolo Bonzini targeting multiple architectures. The ARM64 updates include a workaround for ARM erratum 4193714 affecting protected guests, fixes for 52-bit virtual address handling in nested virtualization, and corrections to guest memory file descriptor permission faults. The x86 improvements address nested virtualization issues, specifically disabling L0's PAUSE loop exiting while L2 guests are running, and fix MOVNTDQA instruction emulation. A notable addition is a new module parameter allowing administrators to disable CET virtualization due to reported host hangs.
The second merge from Mike Rapoport addresses live update system fixes, focusing on kexec handover operations. Key improvements include skipping KHO for crash kernels, enhanced error reporting in memory file descriptor preservation, and validation to prevent preserving files whose page counts exceed UINT_MAX.
Paolo Bonzini also committed a standalone patch introducing the CET disable module parameter, directly responding to proxmox reports of host system hangs during CET virtualization operations.
What's next: These KVM fixes should stabilize virtualization environments experiencing the reported issues. The live update improvements enhance system reliability during kernel updates without reboot.
That's your kernel update. We'll be back tomorrow with the latest development activity.