attempting to read an address that isn?t currently mapped

NTDEV
1

I am not able to understand whats the meaning of
“attempting to read an address that isn?t currently mapped and therefore is not a
valid memory location”

somebody please explain .

2

A page in the virtual address space is either mapped to an actual physical page, and thus accessible, or not mapped, and thus any access will cause a GPF - General Protection Fault.