The release of the QEMU 7.0 project is presented. As an emulator, QEMU allows you to run a program built for one hardware platform on a system with a completely different architecture, for example, run an ARM application on an x86-compatible PC. In the virtualization mode in QEMU, the performance of code execution in an isolated environment is close to a hardware system due to the direct execution of instructions on the CPU and the use of the Xen hypervisor or KVM module.
The project was originally created by Fabrice Bellard to allow Linux executables built for the x86 platform to run on non-x86 architectures. Over the years of development, full emulation support has been added for 14 hardware architectures, the number of emulated hardware devices has exceeded 400. In preparation for version 7.0, more than 2500 changes have been made from 225 developers.
Key improvements added in QEMU 7.0:
- The x86 emulator adds support for the Intel AMX (Advanced Matrix Extensions) instruction set implemented in the Intel Xeon Scalable server processors. AMX offers new custom TMM "TILE" registers and instructions for manipulating data in these registers, such as TMUL (Tile matrix MULtiply) for matrix multiplication.
- Provided the ability to log ACPI events from the guest system through the ACPI ERST interface.
- Support for security labels has been improved in the virtiofs module, which is used to forward part of the host environment's file system to the guest system. Fixed vulnerability CVE-2022-0358, allowing to elevate your privileges in the system by creating executable files in directories forwarded through virtiofs, belonging to another group and equipped with the SGID flag.
- The flexibility of backing up active system images in progress has been improved (a snapshot is created, after which a copy-before-write (CBW) filter is applied to update the state of the snapshot, copying data from areas in which the guest system writes). Added support for images in formats other than qcow2. The ability to access a snapshot with a backup is provided not directly, but through the snapshot-access block device driver. The possibilities for controlling the operation of the CBW filter have been expanded, for example, certain bitmaps can be excluded from processing.
- ARM emulator for 'virt' machines added support for virtio-mem-pci, guest CPU topology detection, and enabling PAuth when using a KVM hypervisor with an hvf accelerator. Added support for PMC SLCR and OSPI Flash controller emulation in the 'xlnx-versal-virt' board emulator. New CRF and APU control models have been added for 'xlnx-zynqmp' emulated machines. Added emulation of FEAT_LVA2, FEAT_LVA (Large Virtual Address space) and FEAT_LPA (Large Physical Address space) extensions.
- Classic TCG (Tiny Code Generator) has dropped support for hosts with ARMv4 and ARMv5 CPUs that do not support unaligned memory access and do not have enough RAM to run QEMU.
- The RISC-V architecture emulator adds support for the KVM hypervisor and implements Vector 1.0 vector extensions, as well as the Zve64f, Zve32f, Zfhmin, Zfh, zfinx, zdinx, and zhinx{min} instructions. Added support for loading OpenSBI (RISC-V Supervisor Binary Interface) binary files for emulated 'spike' machines. For emulated 'virt' machines, the ability to use up to 32 processor cores and support for AIA is implemented.
- The HPPA architecture emulator provides up to 16 vCPUs and improved graphics driver for HP-UX VDE/CDE user environments. Added the ability to change the boot order for SCSI devices.
- Added support for using up to 4 CPU cores, loading an external initrd image and automatically generating a device tree for a bootable core in the OpenRISC architecture emulator for 'sim' boards.
- The PowerPC architecture emulator for emulated 'pseries' machines has implemented the ability to run guest systems under the control of a nested KVM hypervisor. Added support for the spapr-nvdimm device. Added support for XIVE2 interrupt controller and PHB5 controllers for 'powernv' emulated machines, improved support for XIVE and PHB 3/4.
- Support for z390 extensions (Miscellaneous-Instruction-Extensions Facility 15) has been added to the s3x architecture emulator.
Source: opennet.ru