Stack overflow may not be caught in FreeRTOS projects on devices that support TrustZone

[kjassmann-renesas]

Issue

In a TrustZone non-secure FreeRTOS project, if a stack overflow occurs in the PendSV_Handler (which adds up to 40 bytes to the stack), it does not generate an STKOF UsageFault.

In a flat FreeRTOS project on MCUs that support TrustZone, stack overflows of the process stack do not generate an STKOF UsageFault.

Workaround

Allocate at least 40 bytes more for the stack than the maximum stack used by the thread.