Question

Say you are running a program along with many other programs in a modern computer. For some reason, your program runs into a deadlock and never comes out of that. How does the OS deal with such deadlock

Answer 1

The OS deals with such deadlock to temporarily prevent resources from deadlocked processes. It is either it back off a process to some check point allowing preemption of a needed resource and restarting the process at the checkpoint later. Finally, successively kill processes until the system is deadlock free.