Emacs locks up

[Joe Riel]

I've written a debugger controlled by Emacs.  It uses make-network-process
to communicate with a client over TCP.  Works fine on linux and Windows.
However, when running the client in Windows 10 in virtualbox, with Emacs
running on the host system (linux), occasionally Emacs locks up.

When that occurs I have to kill Emacs---it is otherwise unresponsive.  
Have no good idea how to fix or debug this.  Just being able to restore Emacs 
without killing it would be useful.  Any suggestions are appreciated.

-- 
Joe Riel