The Xen Project has released version 4.21 of its open-source virtualization platform. This update includes support for AMD CPPC and Resizable BAR, alongside improvements to x86 runtime and Arm security. It also introduces early RISC-V support, targeting applications in cloud, data centers, automotive, and embedded systems.
On November 19, 2025, the Linux Foundation announced the release of Xen 4.21, the latest version from the Xen Project (@xen_org). This update focuses on advancing open-source virtualization capabilities.
Key features include AMD CPPC support and Resizable BAR support, which enhance hardware utilization on x86 systems. The release improves x86 runtime performance and bolsters Arm security measures. Additionally, it adds early support for RISC-V architecture, expanding compatibility for emerging hardware.
According to the announcement, Xen 4.21 'raises the bar for open source virtualization across cloud, data center, automotive, and embedded systems.' Users can download version 4.21 and access further details via the provided link.
Phoronix reported the release emphasizing the AMD CPPC and Resizable BAR integrations, aligning with the broader enhancements outlined by the Linux Foundation.