Thoughts and clarifications

If you are a Rust programmer, you are not forced to upgrade to the latest and greatest crate. You could just keep using the old crate, it's still published, you can still download it, and unless you have security issue, there's no issue for you. You can even use multiple versions of the same crate in the same project, and it just works. This is the opposite of move fast and break things. It is rather move fast, keep old things working the way they were.

Moreover, kernel developers don't gratuitously use crates like your comment would seem to imply. The vast majority of crates are simply unusable in the kernel because they depend on the standard library. And the standard library cannot be linked into the kernel because the standard library has some requirements regarding memory allocation that cannot be fulfilled by the kernel.

I find it absolutely amazing that you can add a few YAML lines to your GitHub project and there's an entire computer network that will automatically upgrade all of your crates in your Rust project that's on GitHub. And then subsequently your CI fires and everything is tested so that you know all the upgrade didn't break anything. I used that all the time. But this is absolutely unrepresentative of how kernel development with Rust code is done. Maybe someday that will be the case. Maybe in 25 years. We're not even close to that. We need to get even a few crates going in the kernel before that's even a concern in anyone's radar.

If anything, Rust in the kernel is actually move slow. And if we are to conclude anything from the rust for Linux developers' contributions to the Linux kernel, it has been move slow and fix other people's things.