続 No-Execute bit
long mode でのアドレス変換の図、初めて見たとき思わず笑っちゃったよ。
ページサイズ 4Kbyte の場合。
Virtual Address
63 48 47 39 38 30 29 21 20 12 11 0
+-------------+----------------+----------------+----------------+----------------+-------------+
| | Page-Map | Page- | Page-Directory | Page-Table | Physical- |
| Sign Extend | Level-4 Offset | Directory- | Offset | Offset | Page Offset |
| | (PML4) | Pointer Offset | | | |
+-------------+----------------+----------------+----------------+----------------+-------------+
|9 |9 |9 |9 |12
| | Page- | | |
| Page-Map | Directory- | Page- | | 4Kbyte
| Level-4 | Pointer | Directory | Page | Physical
| Table | Table | Table | Table | Page
| +---------+ | +---------+ | +---------+ | +---------+ | +---------+
| | | | | | | | | | | | | | |
| | | | | | | | | | +---------+ 52 | | |
| | | | | | | | | +>| PTE |-+ | | |
| | | | | | | | | +---------+ | | | |
| | | | | | | | | | | | | | |
| | | | +---------+ 52 | | | | | | | | |
| | | +>| PDPE |-+ | | | | | | | | |
| | | +---------+ | | | | | | | | +---------+
| +---------+ 52 | | | | | | | | | +>| Physical|
+>| PML4E |-+ | | | | | | | | | | Address |
+---------+ | | | | | | | | | | +---------+
| | | | | | | | | | | | | |
| | | | | | | +---------+ 52 | | | | |
| | | | | | +>| PDE |-+ | | | | |
| | | | | | +---------+ | | | | | |
| | | | | | | | | | | | | |
+-------------->+---------+ +--->+---------+ +--->+---------+ +--->+---------+ +--->+---------+
|
| 63 52 51 12 11 0
| +--------------+-------------------------------+---------------+
+-| | Page-Map Level-4 Base Address | | CR3
+--------------+-------------------------------+---------------+
