Executing hardware hot-swap typically means telling the system that a component is going down. Then the system moves those resources to the other component to gracefully allow you to remove it without a restart.

Like it's not a case where you just yank out a CPU as you like as though it were a spindle in a RAID-6 array. Especially if there's only one CPU. The state machine can't maintain state if the only component that tracks and maintains state goes missing.