vsock

Package vsock provides access to Linux VM sockets (AF_VSOCK) for communication between a hypervisor and its virtual machines. MIT Licensed.

For more information about VM sockets, check out my blog about Linux VM sockets in Go.

Stability

At this time, package vsock is in a pre-v1.0.0 state. Changes are being made which may impact the exported API of this package and others in its ecosystem.

The general policy of this package is to only support the latest, stable version of Go. Compatibility shims may be added for prior versions of Go on an as-needed basis. If you would like to raise a concern, please file an issue.

If you depend on this package in your applications, please vendor it or use Go modules when building your application.

Requirements

To make use of VM sockets with QEMU and virtio-vsock, you must have:

• a Linux hypervisor with kernel 4.8+
• a Linux virtual machine on that hypervisor with kernel 4.8+
• QEMU 2.8+ on the hypervisor, running the virtual machine

Before using VM sockets, following modules must be removed on hypervisor:

• modprobe -r vmw_vsock_vmci_transport
• modprobe -r vmw_vsock_virtio_transport_common
• modprobe -r vsock

Once removed, vhost_vsock module needs to be enabled on hypervisor:

• modprobe vhost_vsock

On VM, you have to enable vmw_vsock_virtio_transport module. This module should automatically load during boot when the vsock device is detected.

To utilize VM sockets, VM needs to be powered on with following -device flag:

• -device vhost-vsock-pci,id=vhost-vsock-pci0,guest-cid=3

Check out the QEMU wiki page on virtio-vsock for more details. More detail on setting up this environment will be provided in the future.

Usage

To try out VM sockets and see an example of how they work, see cmd/vscp. This command shows usage of the vsock.ListenStream and vsock.DialStream APIs, and allows users to easily test VM sockets on their systems.