Context

In embedded software on NXP MCUs such as the S32K or i.MX RT family, a critical section protects shared state from being modified concurrently by interrupt handlers.

Question

Explain how to prevent an interrupt from disrupting a critical section of code. Your answer should address:

1. What a critical section is and why an interrupt can corrupt shared state.
2. How interrupt masking or temporarily disabling interrupts works in practice.
3. How to restore the previous interrupt state safely, and what risks exist if interrupts stay disabled too long.

Scope guidance

Focus on low-level programming behavior rather than RTOS theory. The interviewer expects a practical systems explanation, including common MCU patterns such as saving the current interrupt state, disabling interrupts, executing the protected code, and restoring the original state afterward.