An equivalent of Looking Glass where VM side runs Linux?

[Looking Glass](https://looking-glass.io/) is an open source application that allows the use of a KVM configured with a passthrough GPU without an attached physical monitor, keyboard or mouse. In Looking Glass terminology, the *host software* is the term for the piece of Looking Glass that runs in the VM *guest* (the VM where the GPU is used). The *client software* is the term for the piece that runs on the Linux *host*, showing the rendered frames. The Looking Glass host is currently Windows-only, and covers the main use case: run Windows-only GPU-heavy software in a Windows VM, showing the result on the Linux host. I have a slightly different use case: I pass my beefier headless GPU through from a Linux host to a *Linux* VM guest. It works fine there for GPU computations based on OpenCL or CUDA or whatever. I'd also like to be able to run 3D software on that Linux VM guest, and display the result on my Linux host. Thus: Is there an equivalent technology for a Linux guest on a Linux host? Or, alternatively, are there any Looking Glass hosts for Linux?