The kernel's extended BPF is in fact an entire virtual machine and so necessarily has a virtual machine language. Arguably it would be better if that software was written in a language intended to be translated into eBPF rather than in C, C++ or Rust compiled for the eBPF virtual machine.

EtA: Also, while the kernel does have some mechanisms which exist elsewhere, the kernel also has its own memory model, distinct from the C++ (and eventually C) memory model, because Linux has been here a long time and needed a model before C++ had one. So this means there's a conflict between what the ISO document says (based on its memory model) and how Linux works (based on its memory model).

So it might be easier on folks if the Linux memory model wasn't just a different memory model for the C language which already has a memory model. That applies just as well for Rust.