https://doc.rust-lang.org/style-guide/index.html#small-items

We leave it to individual tools to decide on exactly what small means. In particular, tools are free to use different definitions in different circumstances.

What does this mean?

What does Linus when he says rustfmtcheck? cargo fmt check? A util I can't find with a simple search? Maybe they have makefile targets or sth for it?

The concerns raised by Linus make sense to me, but should be simple to solve. The small items description already mentions variance, and the need for tools to decide. So shouldn't it be a simple configuration change?