I was a dev on the Visual Studio and Windows teams in the 90s. I’m retired but mentor CS students at two local universities.
I haven’t had a student in two years that was even remotely interested in ring-0, internals, or really understanding a debugger.
I’m not being critical; they are just focused on higher level abstractions.
It’s fun to understand just for intellectual curiosity’s sake but the number of people who get to work on shipping code where ring-0 knowledge is useful has to be minuscule as a percentage. It feels like a minor miracle I got to work on device drivers in my career. I imagine students might be more worried about completing assignments and good grades than the ins and outs of debuggers, too, though understanding those is important for problems one is more likely to come across in work projects versus smaller school assignments.
> the number of people who get to work on shipping code where ring-0 knowledge is useful has to be minuscule as a percentage
I wonder if it it is more that the percentage of people who choose to dedicate themselves to that type of work is miniscule. I work in graphics and performance, and it seems similar.
Few people really work on it specifically at any given company, and I've heard people warn others that there are few jobs in it.
But video game companies really want people for those roles and will pay well because they're hard to find. Still, few programmers show any interest in specializing in those skills. If you're passionate about it and willing to learn the details you'll eventually find a lot of job opportunities. I know people who want to work with this and do so - I know many more who have specifically said they want to stay away from it. I don't know anyone who wants to and can't.
How would one start learning about it?
Arguably the lower level abstractions are more interesting too! how exactly Windows does ring-0 is less interesting than writing your own ring-0! And unless you care about writing driver-level software for Windows or contributing to the kernel, learning this is also less useful.
I'm essentially arguing that unless you work at MSFT, there's next to no reason to learn that specific abstraction layer.
Speaking of debuggers...
I still twitch whenever someone says "use ddd" and they are not referring to Evans' seminal work.
:-D