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Global Descriptor Table: Difference between revisions
formatted rest of tables
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{| class="wikitable"
|+ GDT Descriptor (GDTR)
!style="width: 60%; text-align: left; border-right: none;" |79 (64-bit mode)
!style="width: 6%; text-align: right; vertical-align: bottom; border-left: none;" |16
!style="width: 17%; text-align: left; vertical-align: bottom; border-right: none;" |15
!style="width: 17%; text-align: right; vertical-align: bottom; border-left: none;" |0
|-
|style="border-right: none;" |'''Offset'''<br>63 (64-bit mode)
|style="text-align: right; vertical-align: bottom; border-left: none;" |
|style="border-right: none;" |'''Size'''<br><br>15
|style="text-align: right; vertical-align: bottom; border-left: none;" |
|}
* '''Size:''' The size of the table in bytes subtracted by 1. This subtraction occurs because the maximum value of '''Size''' is 65535, while the '''GDT''' can be up to 65536 bytes in length (8192 entries). Further, no '''GDT''' can have a size of 0 bytes.
Line 81:
!style="text-align: right; border-left: none;"|0
|-
|colspan=5 style="
|style="text-align: right; border-left: none;"|<br>0
|colspan=3 style="
|style="text-align: right; border-left: none;"|<br>0
|}
Line 94:
For more information, see '''Section 3.4.5: Segment Descriptors''' and '''Figure 3-8: Segment Descriptor''' of the Intel Software Developer Manual, Volume 3-A.
{| class="wikitable
|+ Access byte
|-
!style="width: 12.5%;"|7
!style="width: 12.5%;"|4
!style="width: 12.5%;"|3
!style="width: 12.5%;"|2
!style="width: 12.5%;"|1
!style="width: 12.5%;"|0
|-
|'''Pr'''
|colspan=2 |'''Privl'''
|'''S'''
|'''Ex'''
|'''DC'''
|'''RW'''
|'''Ac'''
|}
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* '''Ac:''' Accessed bit. Best left clear ('''0'''), the CPU will set it when the segment is accessed.
{| class="wikitable
|+ Flags
|-
!style="width: 25%;"|3
!style="width: 25%;"|2
!style="width: 25%;"|1
!style="width: 25%;"|0
|-
|'''Gr'''
|'''Sz'''
|'''L'''
|Reserved
|}
| |||