QEMU version 4.2.0 released

We would like to announce the availability of the QEMU 4.2.0 release. This release contains 2200+ commits from 198 authors.

You can grab the tarball from our download page. The full list of changes are available in the Wiki.

Highlights include:

• TCG plugin support for passive monitoring of instructions and memory accesses
• block: NBD block driver now supports more efficient handling of copy-on-read requests
• block: NBD server optimizations for copying of sparse images, and general fixes/improvements for NBD server/client implementations
• block/crypto: improved performance for AES-XTS encryption for LUKS disk encryption
• vfio-pci support for “failover_pair_id” property for easier migration of VFIO devices
• virtio-mmio now supports virtio-compatible v2 personality and virtio 1.1 support for packed virtqueues
• 68k: new “next-cube” machine for emulating a classic NeXTcube
• 68k: new “q800” machine for emulating Macintosh Quadro 800
• ARM: new “ast2600-evb” machine for emulating Aspeed AST2600 SoC
• ARM: semihosting v2.0 support with STDOUT_STDERR/EXIT_EXTENDED extentions
• ARM: KVM support for more than 256 CPUs
• ARM: “virt” machine now supports memory hotplugging
• ARM: improved TCG emulation performance
• ARM: KVM support for SVE SIMD instructions on SVE-capable hardware
• PowerPC: emulation support for mffsce, mffscrn, and mffscrni POWER9 instructions
• PowerPC: “powernv” machine now supports Homer and OCC SRAM system devices
• RISC-V: “-initrd” argument now supported
• RISC-V: debugger can now see all architectural state
• s390: emulation support for IEP (Instruction Execution Protection)
• SPARC: “sun4u” IOMMU now supports “invert endianness” bit
• x86: VMX features can be enabled/disabled via “-cpu” flags
• x86: new “microvm” machine that uses virtio-mmio instead of PCI for use as baseline for performance optimizations
• x86: emulation support for AVX512 BFloat16 extensions
• x86: new CPU models for Denverton (server-class Atom-based SoC), Snowridge, and Dhyana
• x86: macOS Hypervisor.framework support (“-accel hvf”) now considered stable
• xtensa: new “virt” machine type
• xtensa: call0 ABI support for user-mode emulation
• and lots more…

Thank you to everyone involved!