The release of the project Qemu 9.1 has been presented. Qemu, as an emulator, enables the launching of programs designed for one hardware platform on a system with a different architecture, such as executing an ARM program on an X86-compatible PC. In virtualization mode, Qemu offers performance close to the hardware system by directly executing instructions on the CPU and utilizing the XEN hypervisor or KVM module in Linux, or the NVMM module in NetBSD.
Originally created by Fabrice Bellard to allow the execution of X86 Linux executable files on non-X86 architectures, the Qemu project has expanded over the years to support full emulation for 14 hardware architectures and over 400 emulated hardware devices. The latest version, 9.1, saw over 2,800 changes contributed by 263 developers.
Key improvements introduced in Qemu 9.1 include:
- Enhanced support for data compression acceleration during guest system migration using IAA technology or UADK. Improved post-migration recovery support in postcopy migrations.
- Added support for virtio_f_notification_data in the Virtio mechanism for guest-host interaction, enabling guest systems to transmit additional data along with notifications, useful for debugging or performance optimization.
- Introduced Guest-Network-Get-Route command for Linux systems and Guest-SSH-* commands for Windows systems in Guest-Agent. Command line interface now allows configurations for “Allowed” and “Blocked” operations.
- In the ARM emulator, support for various processor extensions and SMMUV3 memory control unit enhancements were implemented. Xilinx Zynq boards now support multi-processor configurations, DM163 display controller, and cache controller emulation.
- Loongarch emulator now supports direct loading of kernels in ELF format and allows up to 256 CPUs using Extioi expansion. Debugging capabilities have also been improved.
- For RISC-V architecture emulation, support for various processor extensions and privileged set of commands specifications have been added. Debugging features have been enhanced as well.