The Case for Writing a Kernel in Rust [pdf]
This is good work. I enjoyed reading it. I wonder, though, why Muen separation kernel wasn't mentioned in related work on kernels in safe languages. It uses the SPARK language so that it's provably immune to a number of defects. The Ada compilers can also give you as little or much runtime as you want with several "profiles" available. Muen uses the "minimal, Zero-Runtime" profile. Rust improves on Ada and SPARK with the affine types giving temporal safety plus more flexible model for safe concurrency than Ravenscar. CompSci work shows one can probably do that and info-flow security with contracts but that would be extra, specialist work for Ada/SPARK versus what's built-in to Rust already. Verbose, too.https://muen.codelabs.ch/When I about the Rust kernels, I assumed there would be some trusted components in there which could screw them up on assurance side. Aside from full formal verification, one thing someone might want to try is writing those pieces in SPARK like Muen does. Make a direct port from any proven SPARK to Rust source. Alternatively, compile the SPARK into executable code that Rust calls with its FFI since C code can call SPARK code. Then, those untrusted portions are shown safe with one set of rules while the rest is shown safe with Rust's compiler. Optionally, convert those to an intermediate language of CompCert or CakeML compilers for certified compilation. This is how my Brute-Force Assurance model would attempt to handle each's limitations in a kernel project.Note: Only problem with using SPARK for that is the person doing it probably has to buy a license if the Rust kernel in question isn't GPL. SPARK is only free for use with GPL code. Frama-C is another option one might use to avoid that but SPARK is stronger offering.