QEMU 10.1 released with new CPU features and improved ARM nested virtualization under KVM

QEMU 10.1 is now available, representing a new milestone with over 2,700 commits contributed by 226 authors. While maintaining its core as an open source machine emulator, this release introduces key advances in confidential computing, migration, and platform coverage.

VFIO in QEMU now adds initial support for accessing and mapping memory for confidential guests when guest_memfd is used. This step enables pass-through support for virtual machines operating under Secure Encrypted Virtualization Secure Nested Paging (SEV-SNP) and Intel Trust Domain Extensions (TDX). Live migration workflows benefit from faster post-copy migration thanks to multifd support, alongside optimizations for pre-copy migration. There is now Remote Direct Memory Access (RDMA) migration support for environments using IPv6.

Expanding monitoring capabilities, the QEMU guest agent for Windows virtual machines introduces the ability to query system load through the new guest-get-load command. On hardware support, ARM targets now include new CPU features such as FEAT_SME2 and FEAT_SVE2p1. The platform also adds several new board and machine models and enhances the virt board with nested virtualization, KVM, CXL, and ACPI-based PCI hotplug support.

Following architecture improvements, RISC-V gains new instruction set architecture (ISA) support and the Kunminghu CPU and platform, while x86 KVM brings confidential guest support via TDX and the IGVM file format.