Resolved! STM32H755 stalling CPU when erasing bank 1 flash from code running in bank 2 (but not the other way around)
I am implementing a firmware-update mechanism on STM32H755 (Nucleo board, MCU rev U) in which the two flash banks are independent. New firmware is flashed by erasing the "other" bank (which is always mapped at 0x0810 0000 and accessed with the ____2...