本系列博客用来记录自己对x86体系结构的学习总结，同时方便大家查阅，节省大家学习的时间。

system-programming overview

一句话,(CPL=0), privileged software

1.1 Memory Model

1. backward-compatible with legacy memory model.
2. hardware-translation mechanisms for VA to PA.
3. long mode, falt-memory model.
4. legacy mode, the architecture implements all legacy memory models.

   1.1.1 Memory Addressing

5. Logical addr reference into a segmented-addr space Logical Addr = Segment Selector : Offset (Far pointers) ?

6. Effective addr, or segmetns offsets, which are a portion of the logical addr Effective Address = Base + (Scale x Index ) + Displacement (Near pointers) ?

7. linear(virtual) address Linear Address = Segment Base Addr +Effective Address

8. Physical addr

1.1.2 Memory Organization

Virtual Memory

1. Protected Mode (32bits virtual addr)
2. Long Mode (64bits virtual addr) Physical Memory
3. Real-Address Mode real mode, 1M bytes of physical address space using 20bits physical addr.
4. Legacy Protected Mode
5. Long Mode

1.2 Memory Management