I have a new blog post out on the Intel Developer Zone, about the Simics 6 device register coverage feature. I use device register coverage to look at how different operating systems use the same hardware. The differences are significant, demonstrating the (rather expected) observation that different software stacks use the same hardware in different ways.
The blog post is more of a quick test and demo than a deeper investigation – there is a lot more that could be learned by trying to do things like actually running network applications, or by comparing the driver source code between different Linux kernel versions.
Anyway, the story is here: https://software.intel.com/en-us/blogs/2019/08/29/simics-6-looking-at-how-software-uses-hardware