Q: What does it mean for an Open vSwitch release to be LTS (long-term support)?

A: All official releases have been through a comprehensive testing process and are suitable for production use. Planned releases occur twice a year. If a significant bug is identified in an LTS release, we will provide an updated release that includes the fix. Releases that are not LTS may not be fixed and may just be supplanted by the next major release. The current LTS release is 2.13.x.

For more information on the Open vSwitch release process, refer to Release Process.

Q: What Linux kernel versions does each Open vSwitch release work with?

A: The following table lists the Linux kernel versions against which the given versions of the Open vSwitch kernel module will successfully build. The Linux kernel versions are upstream kernel versions, so Linux kernels modified from the upstream sources may not build in some cases even if they are based on a supported version. This is most notably true of Red Hat Enterprise Linux (RHEL) kernels, which are extensively modified from upstream.

Open vSwitch userspace should also work with the Linux kernel module built into Linux 3.3 and later.

Open vSwitch userspace is not sensitive to the Linux kernel version. It should build against almost any kernel, certainly against 2.6.32 and later.

Open vSwitch branches 2.10 through 2.14 will still compile against the RHEL and CentOS 7 3.10 based kernels since they have diverged from the Linux kernel.org 3.10 kernels.

Starting with Open vSwitch 2.15, building the Linux kernel module from the Open vSwitch source tree is deprecated. It will not be updated to support Linux versions later than 5.8. We will remove the kernel module source code from the Open vSwitch source tree for the Open vSwitch 2.18 release.

更详细的可以看：Releases — Open vSwitch 2.16.90 documentation