How to know whether address is virtual or physical?

Question

Is there any way to know whether the address is physical or virtual if address length of virtual is equal to physical,like 64-bit. For example, my mips processor is 64 bit and it is using 4GB of virtual memory.

Answer 1

If your CPU and OS provide a virtual memory system then every address your program deals with is going to be a virtual address. It is not going out map onto any specific physical memory location.

In such a system to gain access to a particular physical memory location you have to in effect write a device driver. Very few mainstream OSes allow unfettered access to physical memory to user space programs; that would completely break all of their security mechanisms!