Maybe the more regularly used kernel code has a lot of low-hanging security topics shaken out of it already.

And second, I'm indeed wondering what a good path to minimize the loadable kernel code is on a system looks like. My container hosts for example have a fairly well defined set of requirements, and IPSec certainly is not in there. So why not block everything solely made to support IPSec? I'm sure there is more than that.

After all, the most reliable way to higher security is to do less things.

Transitioning components to rust eliminates certain categories of bugs leaving the rest of the bugs to be dealt with.

We'd likely end up needing another language with stronger type and effect systems to eliminate more categories of bugs. Probably something which enforces linear types, capabilities, units of measure types, and effects.

And you'd have to update linux itself to switch to capabilities.