A timeout expires while awaiting a spawn_blocking task that has started. What can the cal…

A timeout expires while awaiting a spawn_blocking task that has started. What can the caller safely conclude?

1. Only that the wait exceeded its deadline; the blocking closure may still finish.
2. The closure was stopped before its next machine instruction.
3. Any database transaction started by the closure was rolled back.
4. Dropping the JoinHandle waits for the closure in the background.