Stack overflow detection (method 1 and 2) in FreeRTOS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is Stack Overflow Detection Method 1 in FreeRTOS?

Method 1 checks the current stack pointer against the stack limits during context switches. If the stack pointer goes beyond the allowed stack area, an overflow is detected.

beginner

How does Stack Overflow Detection Method 2 work in FreeRTOS?

Method 2 uses a known pattern (a 'canary' value) placed at the end of the stack. FreeRTOS checks if this pattern is overwritten to detect stack overflow.

intermediate

Which FreeRTOS configuration option enables Stack Overflow Detection Method 1?

Setting configCHECK_FOR_STACK_OVERFLOW to 1 enables Method 1 stack overflow checking in FreeRTOS.

intermediate

Which FreeRTOS configuration option enables Stack Overflow Detection Method 2?

Setting configCHECK_FOR_STACK_OVERFLOW to 2 enables Method 2 stack overflow checking in FreeRTOS.

intermediate

What is a key difference between Method 1 and Method 2 stack overflow detection in FreeRTOS?

Method 1 checks the actual stack pointer position during context switches for overflow, while Method 2 detects overflow by checking a fixed pattern at stack end.

What does Stack Overflow Detection Method 1 in FreeRTOS rely on?

A Checking the stack pointer during context switches

B A known pattern placed at the stack end

C Using hardware memory protection

D Monitoring CPU usage

Method 1 checks the stack pointer during context switches to detect overflow.

Which configCHECK_FOR_STACK_OVERFLOW value enables Method 2 in FreeRTOS?

A 0

B 1

C 2

D 3

Setting configCHECK_FOR_STACK_OVERFLOW to 2 enables Method 2 stack overflow detection.

When does Method 2 check for stack overflow in FreeRTOS?

A During task creation

B During context switches

C At system startup

D When memory is allocated

Method 2 checks the pattern (canary) during context switches to detect overflow.

What happens if the canary value is overwritten in Method 2?

A Nothing happens

B Task is deleted

C System resets immediately

D Stack overflow is detected

Overwriting the canary value indicates stack overflow in Method 2.

Which method is more precise in detecting stack overflow in FreeRTOS?

A Method 1

B Neither detects overflow

C Both are equally precise

D Method 2

Method 1 is more precise because it checks the actual stack pointer position.

Explain how Stack Overflow Detection Method 1 works in FreeRTOS and how to enable it.

Think about the stack pointer relative to the stack base.

Describe the difference between Method 1 and Method 2 stack overflow detection in FreeRTOS.

Compare how each method detects overflow.