The forced preemption mechanism that uses VM handshakes doesn't care about locks, so it could hypothetically preempt and kill the thread inside the long computa

The forced preemption mechanism that uses VM handshakes doesn't care about locks, so it could hypothetically preempt and kill the thread inside the long computation. If you want to insert explicit interruption checks, that's another matter, and it doesn't require the forced preemption mechanism at all.