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4-28 Vol. 3A

PAGING

.

4.6 ACCESS 

RIGHTS

There is a translation for a linear address if the processes described in Section 4.3, Section 4.4.2, and Section 4.5 
(depending upon the paging mode) completes and produces a physical address. Whether an access is permitted by 
a translation is determined by the access rights specified by the paging-structure entries controlling the transla-
tion;

1

 paging-mode modifiers in CR0, CR4, and the IA32_EFER MSR; EFLAGS.AC; and the mode of the access.

6

3

6

2

6

1

6

0

5

9

5

8

5

7

5

6

5

5

5

4

5

3

5

2

5

1

M

1

NOTES:

1. M is an abbreviation for MAXPHYADDR.

M-1

3

2

3

1

3

0

2

9

2

8

2

7

2

6

2

5

2

4

2

3

2

2

2

1

2

0

1

9

1

8

1

7

1

6

1

5

1

4

1

3

1

2

1

1

1

0 9 8 7 6 5 4 3 2 1 0

Reserved

2

2. Reserved fields must be 0.

Address of PML4 table

Ignored

P

C

D

P

W

T

Ign.

CR3

X

D

3

3. If IA32_EFER.NXE = 0 and the P flag of a paging-structure entry is 1, the XD flag (bit 63) is reserved.

Ignored

Rsvd.

Address of page-directory-pointer table

Ign. Rs

vd

I

g

n

A

P

C

D

P

W

T

U

/S

R

/

W

1 PML4E:

present

Ignored

0

PML4E:

not

present

X

D

Prot.

Key

4

4. If CR4.PKE = 0, the protection key is ignored.

Ignored

Rsvd.

Address of

1GB page frame

Reserved

P

A

T

Ign. G 1 D A

P

C

D

P

W

T

U

/S

R

/

W

1

PDPTE:

1GB

page

X

D

Ignored

Rsvd.

Address of page directory

Ign.

0

I

g

n

A

P

C

D

P

W

T

U

/S

R

/

W

1

PDPTE:

page

directory

Ignored

0

PDTPE:

not

present

X

D

Prot.

Key

4

Ignored

Rsvd.

Address of

2MB page frame

Reserved

P

A

T

Ign. G 1 D A

P

C

D

P

W

T

U

/S

R

/

W

1

PDE:

2MB

page

X

D

Ignored

Rsvd.

Address of page table

Ign.

0

I

g

n

A

P

C

D

P

W

T

U

/S

R

/

W

1

PDE:

page

table

Ignored

0

PDE:

not

present

X

D

Prot.

Key

4

Ignored

Rsvd.

Address of 4KB page frame

Ign. G

P

A

T

D A

P

C

D

P

W

T

U

/S

R

/

W

1

PTE:

4KB

page

Ignored

0

PTE:

not

present

Figure 4-11.  Formats of CR3 and Paging-Structure Entries with IA-32e Paging

1. With PAE paging, the PDPTEs do not determine access rights.