Cloud Hypervisor v24.0 Released!
Posted May 27, 2022 by Cloud Hypervisor Team ‐ 2 min read
This release has been tracked through the v24.0 project.
Bypass Mode for
virtio-iommu specification describes how a device can be attached by default
to a bypass domain. This feature is particularly helpful for booting a VM with
guest software which doesn’t support
virtio-iommu but still need to access
the device. Now that Cloud Hypervisor supports this feature, it can boot a VM
with Rust Hypervisor Firmware or OVMF even if the
virtio-block device exposing
the disk image is placed behind a virtual IOMMU.
Ensure Identifiers Uniqueness
Multiple checks have been added to the code to prevent devices with identical identifiers from being created, and therefore avoid unexpected behaviors at boot or whenever a device was hot plugged into the VM.
Sparse Mmap support
Sparse mmap support has been added to both VFIO and vfio-user devices. This allows the device regions that are not fully mappable to be partially mapped. And the more a device region can be mapped into the guest address space, the fewer VM exits will be generated when this device is accessed. This directly impacts the performance related to this device.
Expose Platform Serial Number
serial_number option has been added to
--platform, allowing a user to
set a specific serial number for the platform. This number is exposed to the
guest through the SMBIOS.
Notable Bug Fixes
- Fix loading RAW firmware (#4072)
- Reject compressed QCOW images (#4055)
- Reject virtio-mem resize if device is not activated (#4003)
- Fix potential mmap leaks from VFIO/vfio-user MMIO regions (#4069)
- Fix algorithm finding HOB memory resources (#3983)
- Refactor interrupt handling (#4083)
- Load kernel asynchronously (#4022)
- Only create ACPI memory manager DSDT when resizable (#4013)
Deprecated features will be removed in a subsequent release and users should plan to use alternatives
mergeableoption from the
virtio-pmemsupport has been deprecated (#3968)
daxoption from the
virtio-fssupport has been deprecated (#3889)
New on the Website
A new blog post Achieving Bare Metal Performance Within a Virtual Machine has been added to the Cloud Hypervisor website.
Many thanks to everyone who has contributed to our release:
- Anatol Belski email@example.com
- Bo Chen firstname.lastname@example.org
- Fabiano Fidêncio email@example.com
- LiHui firstname.lastname@example.org
- Maksym Pavlenko email@example.com
- Rob Bradford firstname.lastname@example.org
- Sebastien Boeuf email@example.com
- Steven Dake firstname.lastname@example.org
- Vincent Batts email@example.com
- Wei Liu firstname.lastname@example.org
See the GitHub Release for the release assets.