Intel 64 and IA-32 Architectures Software Developers Manual Volume 3B, System Programming Guide Part 2

Table Of Contents
24-8 Vol. 3
SUPPORT FOR ADDRESS TRANSLATION
If bit 7 of the EPT PDE is 1, the entry maps a 2-MByte page. Table 24-4 shows the
format of such an EPT PDE.
Table 24-3. Format of an EPT Page-Directory Entry that References an EPT Page
Table
Bit
Position(s)
Contents
0 Read access; indicates whether reads are allowed from the 2-MByte region
controlled by this entry
1 Write access; indicates whether writes are allowed to the 2-MByte region
controlled by this entry
2 Execute access; indicates whether instruction fetches are allowed from the 2-
MByte region controlled by this entry
6:3 Reserved (must be 0)
7 Must be 0 (otherwise, this entry maps a 2-MByte page)
11:8 Ignored
N–1:12 Physical address of 4-KByte aligned EPT page table referenced by this entry
1
51:N Reserved (must be 0)
63:52 Ignored
NOTES:
1. N is the physical-address width supported by the logical processor.
Table 24-4. Format of an EPT Page-Directory Entry that Maps a 2-MByte Page
Bit
Position(s)
Contents
0 Read access; indicates whether reads are allowed from the 2-MByte page
referenced by this entry
1 Write access; indicates whether writes are allowed to the 2-MByte page
referenced by this entry
2 Execute access; indicates whether instruction fetches are allowed from the 2-
MByte page referenced by this entry
5:3 EPT memory type for this 2-MByte page (see Section 24.2.5)
6 Ignore PAT memory type for this 2-MByte page (see Section 24.2.5)