Cloud Hypervisor v39.0 Released!

Posted April 27, 2024 by Cloud Hypervisor Team ‐ 2 min read

This release has been tracked in our roadmap project as iteration v39.0. The following user visible changes have been made:

Variable Sizing of PCI Apertures for Segments

It is now possible to use --pci-segment to adjust the aperture size that devices 32-bit and 64-bit PCI device BARs will be allocated from. Previously the address space was equally distributed across all the segments which may leave insufficient space for devices that require a large 32-bit space. With this change the weighting per segment can be adjusted. (#6387)

Direct Booting with bzImages

Support for directly booting Linux from bzImages has been added.(#6200)

Support for NVIDIA GPUDirect P2P Support

The x_nv_gpudirect_clique option was added to --device to allow the configuration of device P2P support with NVIDIA GPUs. (#6235)

Guest NMI Injection Support

A new API endpoint and ch-remote option added for injecting an NMI into the guest. (#6047)

Notable Bug Fixes

  • Workaround for kernel bug affecting guest IRQ masking on AMD (#6353)
  • Correctly cleanup sigwinch_listener process (#6208)
  • Graceful shutdown of HTTP API thread (#6248, #6247)
  • Fix queue_affinity option in OpenAPI metadata (#6268)
  • Fix documentation to indicate only stream mode is supported by virtio-vsock (#6306)
  • Fix virtio-fs tag validation (#6358, #6359)
  • Add missing pvpanic device to OpenAPI metadata (#6372)
  • Fixes for nested virtualization with VFIO devices (#6110, #6298, #6297, #6319)
  • Fix for backing file for virtio-mem regions with snapshot/restore (#6337, #6338)
  • Explicitly mark FDs used for network devices as invalid across snapshot/restore (#6332, #6286)
  • Improve event-monitor events around reboot (#6277, #6274)
  • Fix potential deadlock around paused devices during live migration (#6293)
  • Fix panic when running ch-remote with no subcommand (#6230)
  • Fix hotplug of virtio devices after snapshot/restore and live migration (#6326, #6265)


Many thanks to everyone who has contributed to our release:


See the GitHub Release for the release assets.