I've dug into this topic in the past and my takeaway for this entire thing was “cool idea, but don't use it practice ”. I.e. just unrwap the lock call's result. If a worker thread panics you should assume your applications done for. Some people even recommend setting panic=abort for release builds, in which case you won't even be able to catch those panics to begin with.

I mean, think about the actual use cases here. On of my threads just panicked. Does it make sense to continue running the application? And if you answer yes, this is an error condition that can occur, then it shouldn't panick to begin with and instead handle errors gracefully, leaving the mutex unpoisoned.