QEMU 4.2 Released With Many Improvements For Linux Virtualization

QEMU 4.2 is out this morning as a key piece of the open-source Linux virtualization stack.

There are many changes to find with QEMU 4.2 to end out 2019 but some of the highlights for this feature update to this leading open-source emulator for hardware virtualization include:

- Support for Intel AVX-512 BFloat16 (BF16) extensions.

- The latest updates of all the CPU models now have TSX (Transactional Synchronization Extensions) extensions disabled by default. This is due to the recent TSX Async Abort vulnerability / Zombieload Variant Two.

- Better performance for Tiny Code Generator (TCG) emulation of ARM cores.

- Another QEMU 4.2 performance improvement can come with recent Gcrypt and Nettle libraries where QEMU can now use the library's own XTS cipher mode and that can result in a big performance boost for AES-XTS encryption particularly if using LUKS disk encryption when running under QEMU.

- The LUKS block driver now supports falloc/full pre-allocation.

- Support for QEMU on ARM to run with more than 256 CPUs.

- ASpeed AST2600 model support.

- Arm SVE (Scalable Vector Extensions) is now supported with KVM guests on capable ARM SoCs and supported kernels.

- The Apple macOS Hypervisor Framework (HVF) support is now considered stable.

More details on QEMU 4.2 via QEMU.org.