Microsoft’s Rust-based OpenVMM is expanding into a broader community-driven virtualisation project, with Intel, Arm and developers contributing to its cross-platform and security capabilities.
Microsoft’s OpenVMM is growing from an open-sourced virtualisation project into a broader community-driven infrastructure effort, with nearly 100 contributors and more than 200 forks. Microsoft open-sourced the Rust-based virtual machine manager in late 2024.
OpenVMM supports Windows, Linux and macOS across x64 and AArch64 systems, with virtualisation backends including Microsoft MSHV, WHP, Linux KVM and Apple’s Hypervisor framework. Intel and Arm have also contributed, strengthening its position as a multi-vendor open-source project.
Recent development includes AArch64 improvements, SMMUv3 emulation, CXL support, PCIe NUMA configuration and newer device-assignment capabilities. Community developers are also exploring OpenVMM as a possible virtual machine manager backend for WSL.
Confidential computing is another major focus. Intel TDX support has reached general availability, while Microsoft says performance overhead fell from around 3% to roughly 1% for certain workloads. Arm CCA Realm support is underway, and AMD SEV-SNP work continues across Virtual NMI, logging, debugging, attestation and sealing.
Microsoft is also using OpenVMM’s Rust foundation as part of its security approach, with much of the virtualisation functionality running in user mode and sandboxing separating sensitive components.
Rather than replacing existing virtual machine managers, Microsoft says OpenVMM is intended to give developers and customers more choice across workloads and environments.
