Implement virtual memory

[anarchuser]

Purpose: Ensures physical isolation and separation between user processes, thus adding a basic level of security

Implementation: Use the MMU and page tables as indirection to separate virtual per-process memory from physical, general-purpose storage. Additionally, create physically separated space for the system only accessible from EL1 and above.

Proof: Multiple user processes see different data at the same virtual adresses. Neither of them can access kernel space.

Bonus: Figure out how to distribute available physical memory to kernel and all user processes

[anarchuser]

Relevant resources:

• https://documentation-service.arm.com/static/5efa1d23dbdee951c1ccdec5?token=
• https://s-matyukevich.github.io/raspberry-pi-os/docs/lesson06/rpi-os.html