A Simple ExampleFirst, I had to take the patches from  and apply them against the ubuntu-utopic kernel, which is based on 3.15-rc8 as of this post. They cherry-picked cleanly and the branch I'm using is stored here . In addition to applying the patches I had to also enable CONFIG_KGRAFT. A pre-built test kernel can be downloaded here .
Next, I created a test VM and installed the test kernel, headers, and build dependencies into that VM and rebooted. Now after a successful reboot, we need to produce an actual patch to test. I've created a github project  with the sample patch; to make it easy to clone and get started.
The code in kgraft_patcher.c is the example found in samples/kgraft . Now we can build it easily using the Makefile I have in my project by typing make.
Next, the module needs to be inserted using the following:
Run the following to see if the module loaded properly:
You'll notice some messages printed with the following:
This means that not all processes have entered the kernel and may not have a "new universe" flag set. Run the following to see which processes still needs to be updated.
An example of this is found in the kgraft-examples  called 'hurryup.sh':
Here is checks for all processes that have 'kgr_in_progress' set and sends a SIGCONT signal to that process.
I've noticed that I had to also send a SIGSTOP followed by a SIGCONT to finally get everything synced up.
Eventually you'll see:
Now your kernel is running the new patch without rebooting!