Does the PIC32MZ have a real MMU that can translate individual virtual pages of 512-4096 bytes into physical addresses, or does it just have a simple MMU like the ARM Cortex-M4 has, which can just set access protections on certain areas of memory?
As an aside, what's the attraction of running Linux on a part like this? Will you have enough resources left to do anything useful after cramming the OS onto the part? What's next, porting Linux to your smart toaster?