External/cloud-hypervisor
1
0
Fork 0
mirror of https://github.com/cloud-hypervisor/cloud-hypervisor.git synced 2024-12-24 22:55:19 +00:00
Code Issues Packages Projects Releases Wiki Activity
097ba3b191
cloud-hypervisor/release-notes.md
Rob Bradford 198bd55122 build, release-notes.md: Document 0.10.0 release 
Update release notes and version number for the new release.

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
2020-09-18 14:06:10 +01:00

36 KiB
Raw Blame History

v0.10.0

This release has been tracked through the 0.10.0 project.

Highlights for cloud-hypervisor version 0.10.0 include:

virtio-block Support for Multiple Descriptors

Some virtio-block device drivers may generate requests with multiple descriptors and support has been added for those drivers.

Memory Zones

Support has been added for fine grained control of memory allocation for the guest. This includes controlling the backing of sections of guest memory, assigning to specific host NUMA nodes and assigning memory and vCPUs to specific memory nodes inside the guest. Full details of this can be found in the memory documentation.

Seccomp Sandbox Improvements

All the remaining threads and devices are now isolated within their own seccomp filters. This provides a layer of sandboxing and enhances the security model of cloud-hypervisor.

Preliminary KVM HyperV Emulation Control

A new option (kvm_hyperv) has been added to --cpus to provide an option to toggle on KVM's HyperV emulation support. This enables progress towards booting Windows without adding extra emulated devices.

Notable Bug Fixes

  • When using ch-remote to resize the VM parameter now accepts the standard sizes suffices (#1596)
  • cloud-hypervisor no longer panics when started with --memory hotplug_method=virtio-mem and no hotplug_size (#1564)
  • After a reboot memory can remove when using --memory hotplug_method=virtio-mem (#1593)
  • --version shows the version for released binaries (#1669)
  • Errors generated by worker threads for virtio devices are now printed out (#1551)

Contributors

Many thanks to everyone who has contributed to our 0.10.0 release including some new faces.

v0.9.0

This release has been tracked through the 0.9.0 project.

Highlights for cloud-hypervisor version 0.9.0 include:

io_uring Based Block Device Support

If the io_uring feature is enabled and the host kernel supports it then io_uring will be used for block devices. This results a very significant performance improvement.

Block and Network Device Statistics

Statistics for activity of the virtio network and block devices is now exposed through a new vm.counters HTTP API entry point. These take the form of simple counters which can be used to observe the activity of the VM.

HTTP API Responses

The HTTP API for adding devices now responds with the name that was assigned to the device as well the PCI BDF.

CPU Topology

A topology parameter has been added to --cpus which allows the configuration of the guest CPU topology allowing the user to specify the numbers of sockets, packages per socket, cores per package and threads per core.

Release Build Optimization

Our release build is now built with LTO (Link Time Optimization) which results in a ~20% reduction in the binary size.

Hypervisor Abstraction

A new abstraction has been introduced, in the form of a hypervisor crate so as to enable the support of additional hypervisors beyond KVM.

Snapshot/Restore Improvements

Multiple improvements have been made to the VM snapshot/restore support that was added in the last release. This includes persisting more vCPU state and in particular preserving the guest paravirtualized clock in order to avoid vCPU hangs inside the guest when running with multiple vCPUs.

Virtio Memory Ballooning Support

A virtio-balloon device has been added, controlled through the resize control, which allows the reclamation of host memory by resizing a memory balloon inside the guest.

Enhancements to ARM64 Support

The ARM64 support introduced in the last release has been further enhanced with support for using PCI for exposing devices into the guest as well as multiple bug fixes. It also now supports using an initramfs when booting.

Intel SGX Support

The guest can now use Intel SGX if the host supports it. Details can be found in the dedicated SGX documentation.

Seccomp Sandbox Improvements

The most frequently used virtio devices are now isolated with their own seccomp filters. It is also now possible to pass --seccomp=log which result in the logging of requests that would have otherwise been denied to further aid development.

Notable Bug Fixes

  • Our virtio-vsock implementation has been resynced with the implementation from Firecracker and includes multiple bug fixes.
  • CPU hotplug has been fixed so that it is now possible to add, remove, and re-add vCPUs (#1338)
  • A workaround is now in place for when KVM reports MSRs available MSRs that are in fact unreadable preventing snapshot/restore from working correctly (#1543).
  • virtio-mmio based devices are now more widely tested (#275).
  • Multiple issues have been fixed with virtio device configuration (#1217)
  • Console input was wrongly consumed by both virtio-console and the serial. (#1521)

Contributors

Many thanks to everyone who has contributed to our 0.9.0 release including some new faces.

v0.8.0

This release has been tracked through the 0.8.0 project.

Highlights for cloud-hypervisor version 0.8.0 include:

Experimental Snapshot and Restore Support

This release includes the first version of the snapshot and restore feature. This allows a VM to be paused and then subsequently snapshotted. At a later point that snapshot may be restored into a new running VM identical to the original VM at the point it was paused.

This feature can be used for offline migration from one VM host to another, to allow the upgrading or rebooting of the host machine transparently to the guest or for templating the VM. This is an experimental feature and cannot be used on a VM using passthrough (VFIO) devices. Issues with SMP have also been observed (#1176).

Experimental ARM64 Support

Included in this release is experimental support for running on ARM64. Currently only virtio-mmio devices and a serial port are supported. Full details can be found in the ARM64 documentation.

Support for Using 5-level Paging in Guests

If the host supports it the guest is now enabled for 5-level paging (aka LA57). This works when booting the Linux kernel with a vmlinux, bzImage or firmware based boot. However booting an ELF kernel built with CONFIG_PVH=y does not work due to current limitations in the PVH boot process.

Virtio Device Interrupt Suppression for Network Devices

With virtio-net and vhost-user-net devices the guest can suppress interrupts from the VMM by using the VIRTIO_RING_F_EVENT_IDX feature. This can lead to an improvement in performance by reducing the number of interrupts the guest must service.

vhost_user_fs Improvements

The implementation in Cloud Hypervisor of the VirtioFS server now supports sandboxing itself with seccomp.

Notable Bug Fixes

  • VMs that have not yet been booted can now be deleted (#1110).
  • By creating the tap device ahead of creating the VM it is not required to run the cloud-hypervisor binary with CAP_NET_ADMIN (#1273).
  • Block I/O via virtio-block or vhost-user-block now correctly adheres to the specification and synchronizes to the underlying filesystem as required based on guest feature negotiation. This avoids potential data loss (#399, #1216).
  • When booting with a large number of vCPUs then the ACPI table would be overwritten by the SMP MPTABLE. When compiled with the acpi feature the MPTABLE will no longer be generated (#1132).
  • Shutting down VMs that have been paused is now supported (#816).
  • Created socket files are deleted on shutdown (#1083).
  • Trying to use passthrough devices (VFIO) will be rejected on mmio builds (#751).

Command Line and API Changes

This is non exhaustive list of HTTP API and command line changes:

  • All user visible socket parameters are now consistently called socket rather than sock in some cases.
  • The ch-remote tool now shows any error message generated by the VMM
  • The wce parameter has been removed from --disk as the feature is always offered for negotiation.
  • --net has gained a host_mac option that allows the setting of the MAC address for the tap device on the host.

Contributors

Many thanks to everyone who has contributed to our 0.8.0 release including some new faces.

v0.7.0

This release has been tracked through the 0.7.0 project.

Highlights for cloud-hypervisor version 0.7.0 include:

Block, Network, Persistent Memory (PMEM), VirtioFS and Vsock hotplug

Further to our effort to support modifying a running guest we now support hotplug and unplug of the following virtio backed devices: block, network, pmem, virtio-fs and vsock. This functionality is available on the (default) PCI based tranport and is exposed through the HTTP API. The ch-remote utility provides a CLI for adding or removing these device types after the VM has booted. User can use the id parameter on the devices to choose names for devices to ease their removal.

Alternative libc Support

Cloud Hypervisor can now be compiled with the musl C library and this release contains a static binary compiled using that toolchain.

Multithreaded Multi Queued vhost-user Backends

The vhost-user backends for network and block support that are shipped by Cloud Hypervisor have been enhanced to support multiple threads and queues to improve throughput. These backends are used automatically if vhost_user=true is passed when the devices are created.

Initial RamFS Support

By passing the --initramfs command line option the user can specify a file to be loaded into the guest memory to be used as the kernel initial filesystem. This is usually used to allow the loading of drivers needed to be able to access the real root filesystem but it can also be used standalone for a very minimal image.

Alternative Memory Hotplug: virtio-mem

As well as supporting ACPI based hotplug Cloud Hypervisor now supports using the virtio-mem hotplug alternative. This can be controlled by the hotplug_method parameter on the --memory command line option. It currently requires kernel patches to be able to support it.

Seccomp Sandboxing

Cloud Hypervisor now has support for restricting the system calls that the process can use via the seccomp security API. This on by default and is controlled by the --seccomp command line option.

Updated Distribution Support

With the release of Ubuntu 20.04 we have added that to the list of supported distributions and is part of our regular testing programme.

Command Line and API Changes

This is non exhaustive list of HTTP API and command line changes

  • New id fields added for devices to allow them to be named to ease removal. If no name is specified the VMM chooses one.
  • Use --memory's shared and hugepages controls for determining backing memory instead of providing a path.
  • The --vsock parameter only takes one device as the Linux kernel only supports a single Vsock device. The REST API has removed the vector for this option and replaced it with a single optional field.
  • There is enhanced validation of the command line and API provided configurations to ensure that the provided options are compatible e.g. that shared memory is in use if any attempt is made to used a vhost-user backed device.
  • ch-remote has added add-disk, add-fs, add-net, add-pmem and add-vsock subcommands. For removal remove-device is used. The REST API has appropriate new HTTP endpoints too.
  • Specifying a size with --pmem is no longer required and instead the size will be obtained from the file. A discard_writes option has also been added to provide the equivalent of a read-only file.
  • The parameters to --block-backend have been changed to more closely align with those used by --disk.

Contributors

Many thanks to everyone who has contributed to our 0.7.0 release including some new faces.

v0.6.0

This release has been tracked through the 0.6.0 project.

Highlights for cloud-hypervisor version 0.6.0 include:

Directly Assigned Devices Hotplug

We continued our efforts around supporting dynamically changing the guest resources. After adding support for CPU and memory hotplug, Cloud Hypervisor now supports hot plugging and hot unplugging directly assigned (a.k.a. VFIO) devices into an already running guest. This closes the features gap for providing a complete Kata Containers workloads support with Cloud Hypervisor.

Shared Filesystem Improvements

We enhanced our shared filesystem support through many virtio-fs improvements. By adding support for DAX, parallel processing of multiple requests, FS_IO, LSEEK and the MMIO virtio transport layer to our vhost_user_fs daemon, we improved our filesystem sharing performance, but also made it more stable and compatible with other virtio-fs implementations.

Block and Networking IO Self Offloading

When choosing to offload the paravirtualized block and networking I/O to an external process (through the vhost-user protocol), Cloud Hypervisor now automatically spawns its default vhost-user-blk and vhost-user-net backends into their own, separate processes. This provides a seamless parvirtualized I/O user experience for those who want to run their guest I/O into separate executions contexts.

Command Line Interface

More and more Cloud Hypervisor services are exposed through the Rest API and thus only accessible via relatively cumbersome HTTP calls. In order to abstract those calls into a more user friendly tool, we created a Cloud Hypervisor Command Line Interface (CLI) called ch-remote. The ch-remote binary is created with each build and available e.g. at cloud-hypervisor/target/debug/ch-remote when doing a debug build.

Please check ch-remote --help for a complete description of all available commands.

PVH Boot

In addition to the traditional Linux boot protocol, Cloud Hypervisor now supports direct kernel booting through the PVH ABI.

Contributors

With the 0.6.0 release, we are welcoming a few new contributors. Many thanks to them and to everyone that contributed to this release:

v0.5.1

This is a bugfix release branched off v0.5.0. It contains the following fixes:

  • Update DiskConfig to contain missing disk control features (#790) - Samuel Ortiz and Sergio Lopez
  • Prevent memory overcommit via virtio-fs (#763) - Sebastien Boeuf
  • Fixed error reporting for resize command - Samuel Ortiz
  • Double reboot workaround (#783) - Rob Bradford
  • Various CI and development tooling fixes - Sebastien Boeuf, Samuel Ortiz, Rob Bradford

v0.5.0

This release has been tracked through the 0.5.0 project.

Highlights for cloud-hypervisor version 0.5.0 include:

Virtual Machine Dynamic Resizing

With 0.4.0 we added support for CPU hot plug, and 0.5.0 adds CPU hot unplug and memory hot plug as well. This allows to dynamically resize Cloud Hypervisor guests which is needed for e.g. Kubernetes related use cases. The memory hot plug implementation is based on the same framework as the CPU hot plug/unplug one, i.e. hardware-reduced ACPI notifications to the guest.

Next on our VM resizing roadmap is the PCI devices hotplug feature.

Multi-Queue, Multi-Threaded Paravirtualization

We enhanced our virtio networking and block support by having both devices use multiple I/O queues handled by multiple threads. This improves our default paravirtualized networking and block devices throughput.

New Interrupt Management Framework

We improved our interrupt management implementation by introducing an Interrupt Manager framework, based on the currently on-going rust-vmm vm-device crates discussions. This move made the code significantly cleaner, and allowed us to remove several KVM related dependencies from crates like the PCI and virtio ones.

Development Tools

In order to provide a better developer experience, we worked on improving our build, development and testing tools. Somehow similar to the excellent Firecracker's devtool, we now provide a dev_cli script.

With this new tool, our users and contributors will be able to build and test Cloud Hypervisor through a containerized environment.

Kata Containers Integration

We spent some significant time and efforts debugging and fixing our integration with the Kata Containers project. Cloud Hypervisor is now a fully supported Kata Containers hypervisor, and is integrated into the project's CI.

Contributors

Many thanks to everyone that contributed to the 0.5.0 release:

v0.4.0

This release has been tracked through the 0.4.0 project.

Highlights for cloud-hypervisor version 0.4.0 include:

Dynamic virtual CPUs addition

As a way to vertically scale Cloud-Hypervisor guests, we now support dynamically adding virtual CPUs to the guests, a mechanism also known as CPU hot plug. Through hardware-reduced ACPI notifications, Cloud Hypervisor can now add CPUs to an already running guest and the high level operations for that process are documented here

During the next release cycles we are planning to extend Cloud Hypervisor hot plug framework to other resources, namely PCI devices and memory.

Programmatic firmware tables generation

As part of the CPU hot plug feature enablement, and as a requirement for hot plugging other resources like devices or RAM, we added support for programmatically generating the needed ACPI tables. Through a dedicated acpi-tables crate, we now have a flexible and clean way of generating those tables based on the VMM device model and topology.

Filesystem and block devices vhost-user backends

Our objective of running all Cloud Hypervisor paravirtualized I/O to a vhost-user based framework is getting closer as we've added Rust based implementations for vhost-user-blk and virtiofs backends. Together with the vhost-user-net backend that came with the 0.3.0 release, this will form the default Cloud Hypervisor I/O architecture.

Guest pause and resume

As an initial requiremnt for enabling live migration, we added support for pausing and resuming any VMM components. As an intermediate step towards live migration, the upcoming guest snapshotting feature will be based on the pause and resume capabilities.

Userspace IOAPIC by default

As a way to simplify our device manager implementation, but also in order to stay away from privileged rings as often as possible, any device that relies on pin based interrupts will be using the userspace IOAPIC implementation by default.

PCI BAR reprogramming

In order to allow for a more flexible device model, and also support guests that would want to move PCI devices, we added support for PCI devices BAR reprogramming.

New cloud-hypervisor organization

As we wanted to be more flexible on how we manage the Cloud Hypervisor project, we decided to move it under a dedicated GitHub organization. Together with the cloud-hypervisor project, this new organization also now hosts our kernel and firmware repositories. We may also use it to host any rust-vmm that we'd need to temporarily fork. Thanks to GitHub's seamless repository redirections, the move is completely transparent to all Cloud Hypervisor contributors, users and followers.

Contributors

Many thanks to everyone that contributed to the 0.4.0 release:

v0.3.0

This release has been tracked through the 0.3.0 project.

Highlights for cloud-hypervisor version 0.3.0 include:

Block device offloading

We continue to work on offloading paravirtualized I/O to external processes, and we added support for vhost-user-blk backends. This enables cloud-hypervisor users to plug a vhost-user based block device like SPDK) into the VMM as their paravirtualized storage backend.

Network device backend

The previous release provided support for vhost-user-net backends. Now we also provide a TAP based vhost-user-net backend, implemented in Rust. Together with the vhost-user-net device implementation, this will eventually become the Cloud Hypervisor default paravirtualized networking architecture.

Virtual sockets

In order to more efficiently and securely communicate between host and guest, we added an hybrid implementation of the VSOCK socket address family over virtio. Credits go to the Firecracker project as our implementation is a copy of theirs.

HTTP based API

In anticipation of the need to support asynchronous operations to Cloud Hypervisor guests (e.g. resources hotplug and guest migration), we added a HTTP based API to the VMM. The API will be more extensively documented during the next release cycle.

Memory mapped virtio transport

In order to support potential PCI-free use cases, we added support for the virtio MMIO transport layer. This will allow us to support simple, minimal guest configurations that do not require a PCI bus emulation.

Paravirtualized IOMMU

As we want to improve our nested guests support, we added support for exposing a paravirtualized IOMMU device through virtio. This allows for a safer nested virtio and directly assigned devices support.

To add the IOMMU support, we had to make some CLI changes for Cloud Hypervisor users to be able to specify if devices had to be handled through this virtual IOMMU or not. In particular, the --disk option now expects disk paths to be prefixed with a path= string, and supports an optional iommu=[on|off] setting.

Ubuntu 19.10

With the latest hypervisor firmware, we can now support the latest Ubuntu 19.10 (Eoan Ermine) cloud images.

Large memory guests

After simplifying and changing our guest address space handling, we can now support guests with large amount of memory (more than 64GB).

v0.2.0

This release has been tracked through the 0.2.0 project.

Highlights for cloud-hypervisor version 0.2.0 include:

Network device offloading

As part of our general effort to offload paravirtualized I/O to external processes, we added support for vhost-user-net backends. This enables cloud-hypervisor users to plug a vhost-user based networking device (e.g. DPDK) into the VMM as their virtio network backend.

Minimal hardware-reduced ACPI

In order to properly implement and guest reset and shutdown, we implemented a minimal version of the hardware-reduced ACPI specification. Together with a tiny I/O port based ACPI device, this allows cloud-hypervisor guests to cleanly reboot and shutdown.

The ACPI implementation is a cloud-hypervisor build time option that is enabled by default.

Debug I/O port

Based on the Firecracker idea of using a dedicated I/O port to measure guest boot times, we added support for logging guest events through the 0x80 PC debug port. This allows, among other things, for granular guest boot time measurements. See our debug port documentation for more details.

Improved direct device assignment

We fixed a major performance issue with our initial VFIO implementation: When enabling VT-d through the KVM and VFIO APIs, our guest memory writes and reads were (in many cases) not cached. After correctly tagging the guest memory from cloud-hypervisor we're now able to reach the expected performance from directly assigned devices.

Improved shared filesystem

We added shared memory region with DAX support to our virtio-fs shared file system. This provides better shared filesystem IO performance with a smaller guest memory footprint.

Ubuntu bionic based CI

Thanks to our simple KVM firmware improvements, we are now able to boot Ubuntu bionic images. We added those to our CI pipeline.

v0.1.0

This release has been tracked through the 0.1.0 project.

Highlights for cloud-hypervisor version 0.1.0 include:

Shared filesystem

We added support for the virtio-fs shared file system, allowing for an efficient and reliable way of sharing a filesystem between the host and the cloud-hypervisor guest.

See our filesystem sharing documentation for more details on how to use virtio-fs with cloud-hypervisor.

Initial direct device assignment support

VFIO (Virtual Function I/O) is a kernel framework that exposes direct device access to userspace. cloud-hypervisor uses VFIO to directly assign host physical devices into its guest.

See our VFIO documentation for more detail on how to directly assign host devices to cloud-hypervisor guests.

Userspace IOAPIC

cloud-hypervisor supports a so-called split IRQ chip implementation by implementing support for the IOAPIC. By moving part of the IRQ chip implementation from kernel space to user space, the IRQ chip emulation does not always run in a fully privileged mode.

Virtual persistent memory

The virtio-pmem implementation emulates a virtual persistent memory device that cloud-hypervisor can e.g. boot from. Booting from a virtio-pmem device allows to bypass the guest page cache and improve the guest memory footprint.

Linux kernel bzImage

The cloud-hypervisor linux kernel loader now supports direct kernel boot from bzImage kernel images, which is usually the format that Linux distributions use to ship their kernels. For example, this allows for booting from the host distribution kernel image.

Console over virtio

cloud-hypervisor now exposes a virtio-console device to the guest. Although using this device as a guest console can potentially cut some early boot messages, it can reduce the guest boot time and provides a complete console implementation.

The virtio-console device is enabled by default for the guest console. Switching back to the legacy serial port is done by selecting --serial tty --console off from the command line.

Unit testing

We now run all unit tests from all our crates directly from our CI.

Integration tests parallelization

The CI cycle run time has been significantly reduced by refactoring our integration tests; allowing them to all be run in parallel.