Cloud Hypervisor v30.0 Released!

Posted February 24, 2023 by Cloud Hypervisor Team ‐ 2 min read

This release has been tracked in our roadmap project as iteration v30.0. The following user visible changes have been made:

Command Line Changes for Reduced Binary Size

The clap crate was replaced by the argh crate to create our command line, which reduced our release binary size from 3.6MB to 3.3MB. There were several syntax changes:

  • All --option=value commands now are --option value.
  • The --disk DISK1 DISK2 command now is --disk DISK1 --disk DISK2.
  • The -vvv command now is -v -v -v

Basic vfio-user Server Support

Our vfio-user crate is extended to provide basic server side support with an example of gpio vfio-user device. This crate now is moved to its own repository under the rust-vmm organization.

Heap Profiling Support

A new building target is added for profiling purposes with examples of heap profiling using dhat gated by the dhat-heap feature.

Documentation Improvements

The documentation on Intel TDX is expanded with details of the building and using TD-Shim, references to TDX Tools, and version information of guest/host kernel/TDVF/TDShim being tested. Also, a new ‘heap profiling’ documentation is added with improvements on the existing ‘profiling’ documentation.

Notable Bug Fixes

  • Close FDs for TAP devices that are provided to VM (#5199, #5206)
  • Set vcpu thread status properly and signal exit_evt upon thread exit (#5211)
  • Populate CPUID leaf 0x4000_0010 (TSC frequency) (#5178, #5179)
  • Inform the TPM guest driver upon failed TPM requests on the host (#5151)
  • Bug fix to OpenAPI specification file (#5186)


Many thanks to everyone who has contributed to our release:


See the GitHub Release for the release assets.