alt Hacker NewsseL4 despite being formally verified contained gnarly bugs, like [1]. Thus, it's not a silver bullet as some people think. Yes, it improves the quality, but only one of the aspects of hardening software, like ASAN, SAST, fuzzing, strict languages, and so on.
> Since it is the unverified SMP config of the kernel
I don't disagree with your point (formal verification does not rid you of all bugs), but this is not the subject of the linked issue. This was a bug in an unverified path.