TODO

1. Paging
  - Relocate kernel?
  - Track owner - kernel/pid
  - Locks?
  - Use first fit - try to free later page tables
  - Bitmap: use ffs and 0:used 1:free

2. Malloc
  - Track usage
    - Use a sorted linked list
  - Above needs a recursion tracker - make sure we don't overflow
    - Use a static var - this might need to become per-pid with threads
  - Doubly linked list of free/malloc'ed areas? is this really necessary?
  - Necessary: merge adjacent free areas - need this to reduce fragmentation
  - Optional: round up <256byte allocs to nearest power of 2 and use a bitmap
    to track allocs

3. FAT
  - Think about: file caches/memory pressure

4. Task switches

5. Scheduler
  - Round robin design initially

5 1/2. Atomic ops/Locks
  - Optional: record spinlock contention
  - Optional: name spinlocks

6. Exceptions/asserts
  - Use ud2 instruction?
  - stack unwinds?

7. Shell
  - Visual memory walker
  - kbd needs work

8. Init
  - Store function pointers in a section, call all functions in that section