devtype_hash is a MurmurHash2 hash of the DEVTYPE= key. If the key isn't present, the value is 0.
svc 0 /* invoke syscall */
，更多细节参见PDF资料
Lean already produces performance comparable to Haskell and OCaml. When higher performance is essential, Lean models can be translated into efficient imperative code embedded in Lean, with clean semantics and without C’s undefined behavior. We are actively working on closing the remaining gap for performance-critical code. The real comparison is not Lean versus C. It is verified code versus unverified code.，这一点在PDF资料中也有详细论述
Лина Пивоварова (редактор отдела Мир)