Rust is making advances here (look at “embedded Rust” efforts). I am curious since I haven’t written kernel code since C went sideways: how easy is it to write

Rust is making advances here (look at “embedded Rust” efforts). I am curious since I haven’t written kernel code since C went sideways: how easy is it to write a driver that has to manipulate registers with arbitrary behavior at arbitrary addresses with modern C compilers and avoid all undefined behavior? I seem to recall Linus has a rant on this.