Xen Project launches Xen 4.22 hypervisor with AMD Zen 5 and RISC‑V enhancements

The Xen Project announced Xen 4.22, a major update to its open‑source type‑1 hypervisor. The release adds several new x86 features, including Flexible Return and Event Delivery (FRED) and AMD Bus Lock Threshold support, and introduces a per‑core temperature command for Intel CPUs. Power management for ARM guests is improved via the Power State Coordination Interface, and the hypervisor now supports the ARM Firmware Framework up to version 1.2.

Xen 4.22 also expands support for emerging hardware, offering specific enhancements for AMD’s upcoming Zen 5 processors and advancing virtualization capabilities for the RISC‑V architecture. Xenstore receives per‑domain quotas and watch‑depth limits to curb excessive resource use, and functional safety testing is bolstered with QEMU‑based fault injection and extended code‑coverage tools.