This hypothetical court-order situation is quite far-fetched. If crates.io was ordered to take down some or all versions of a package, an alternative mirror cou

This hypothetical court-order situation is quite far-fetched. If crates.io was ordered to take down some or all versions of a package, an alternative mirror could easily be created elsewhere and you could configure cargo to use it. But I think the kernel would vendor crate dependencies, partly so that people can build without accessing the network, simply because that's policy in many places.