I've updated to 2.90 the day it came out and don't seem to have the process running.
Using “Activity Monitor” preinstalled in OS X, check whether any process named “kernel_service” is running. If so, double check the process, choose the “Open Files and Ports” and check whether there is a file name like “/Users//Library/kernel_service”. If so, the process is KeRanger’s main process. We suggest terminating it with “Quit -> Force Quit”
Not that Apple is distinctly notable for ransoming your one-time files and applications; on the contrary I've heard more often about people having issues when their Windows / Other OS reaches the end of its support.
edit: It was sarcasm and I know your downvote policies, etc, etc. I just know you guys sometimes roll with the funny punnies, and I was seeing if I had what it took this once. Maybe next time I'll nail a good one though, with a little more creativity and a little more funny to it. Contentless statements can exist here, and I want to learn to make them.
Now there's an aspiration. Reach for the stars, buddy!