Vol. 3A 4-9
PAGING
Figure 4-4 gives a summary of the formats of CR3 and the paging-structure entries with 32-bit paging. For the
paging structure entries, it identifies separately the format of entries that map pages, those that reference other
paging structures, and those that do neither because they are “not present”; bit 0 (P) and bit 7 (PS) are high-
lighted because they determine how such an entry is used.
Figure 4-2. Linear-Address Translation to a 4-KByte Page using 32-Bit Paging
Figure 4-3. Linear-Address Translation to a 4-MByte Page using 32-Bit Paging
0
Directory
Table
Offset
Page Directory
PDE with PS=0
CR3
Page Table
PTE
4-KByte Page
Physical Address
31
21
11
12
22
Linear Address
32
10
12
10
20
20
0
Directory
Offset
Page Directory
PDE with PS=1
CR3
4-MByte Page
Physical Address
31
21
22
Linear Address
10
22
32
18