Xen Project 4.18 Release Notes

Overview

Xen Project 4.18.0 was released on 17th of November 2023.

Xen Project 4.18.0 is the work of 11 months of development.

New Feature Highlights

The list of new features can be found on the following page: Xen Project 4.18 Feature List

You can find information on support status (including security support) for various features in SUPPORT.md and Hypervisor Support Matrix.

Documentation is available online: Xen 4.18 Documentation

Build Requirements

Xen requires gcc v4.1.2 or later (x86), gcc 4.9 or later (arm32), or gcc 5.1 or later (arm64).

Build

First of all you will have to get the Xen 4.18 source code, which you can either download through our release tarball (including signature) from our download page. Alternatively, you can get the source in the following way:

• With a recent enough git (>= 1.7.8.2) just clone and checkout the proper tag (RELEASE-4.18.0) from the xen.git repo directly:

git clone -b RELEASE-4.18.0 https://xenbits.xenproject.org/git-http/xen.git

Build instructions can be found at Compiling Xen From Source or Compiling Xen From Source on NetBSD.

Changes affecting downstreams and users

In general, our aim is to keep old guests working on new versions of Xen, and to allow live migration from the previous Xen major version.

• The old qemu-xen-traditional stubdomain device model (ioemu-stubdom) is deprecated and no longer built by default.

• The old pv-grub Xen fork is also deprecated and no longer built by default. Support to run in PV mode has been added to upstream Grub project.

Known issues

While we do the utmost to make the release perfect, there are always fixes which are not quite complete on time. We will add those here. So if you run into trouble, please check this section.

Currently known issues are:

• Cpupools: when moving a domain from a cpupool with the credit2 scheduler to another cpupool, the host will crash.

• Livepatching: Attempting to apply a livepatch will crash the hypervisor.