Global Descriptor Table: Difference between revisions

changed segment descriptor table
[unchecked revision][unchecked revision]
(corrected styling and removed verbose/useless formatting (e.g. ill-formed css tags that seem to have no effect due to spaces before the semicolon), I'll do the other tables later)
(changed segment descriptor table)
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{| class="wikitable"
|+style="text-align: left;"|'''GDT Descriptor (GDTR):'''
!style="width: 60%; text-align: left; border-right: none;" |79 (64-bit mode) / 48 (32-bit mode)
!style="width: 6%; text-align: right; border-left: none;" |16
!style="width: 17%; text-align: left; border-right: none;" |15
!style="width: 17%; text-align: right; border-left: none;" |0
|-
|style="width: 461px; border-right: none;" |'''Offset'''<br>63 (64-bit mode) / 31 (32-bit mode)
|style="width: 10px; text-align: right; border-left: none;" |<br>0
|style="width: 221px; border-right: none;" |'''Size'''<br>15
|style="width: 11px; text-align: right; border-left: none;" |<br>0
|}
* '''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.
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Each entry in the table has a complex structure:
{| class="wikitable" style="border-width: 3px; width: 640px;"
|+ Segment descriptor
|+style="text-align: left;"|'''SEGMENT DESCRIPTOR:'''
|!style="padding: 2px; width: 15px20%; text-align: rightleft; border-leftright: none;" |1663
|!style="padding: 2px; width: 16px5%; text-align: right; border-left: none;" |056
|!style="padding: 2px; width: 15px7.5%; text-align: right; border-left: none; border-right: 1px none;"|<br>055
|!style="padding: 2px; width: 15px5%; text-align: right; border-left: none; border-right: 1px ;"|<br>1652
|!style="padding: 2px; width: 16px7.5%; text-align: right; border-left: none; border-right: 1px none;"|<br>1651
|!style="padding: 2px; width: 136px5%; text-align: left right; border-left: 1px ; border-right: none;"|'''Base'''<br>2348
|!style="padding: 2px; width: 56px20%; text-align: left ; border-left: 1px ; border-right: none;"|'''Limit'''<br>1947
|!style="padding: 2px; width: 136px5%; text-align: left right; border-left: 1px ; border-right: none;"|'''Access Byte'''<br>740
|!style="paddingwidth: 2px20%; widthtext-align: 296pxleft; border-right: none;" |3139
!style="width: 5%; text-align: right; border-left: none;"|32
|-
|style="padding: 2px; width: 136px; text-align: left ; border-left: 1px ; border-right: none;"|63'''Base'''<br>31
|style="padding: 2px; width: 15px; text-align: right; border-left: none; border-right: 1px ;"|56<br>24
|style="padding: 2px; width: 56px; text-align: left ; border-left: 1px ; border-right: none;"|55'''Flags'''<br>3
|style="padding: 2px; width: 15px; text-align: right; border-left: none; border-right: 1px ;"|52<br>0
|style="padding: 2px; width: 56px; text-align: left ; border-left: 1px ; border-right: none;"|51'''Limit'''<br>19
|style="padding: 2px; width: 15px; text-align: right; border-left: none; border-right: 1px ;"|48<br>16
|style="padding: 2px; width: 136px; text-align: left ; border-left: 1px ; border-right: none;"|47'''Access Byte'''<br>7
|style="padding: 2px; width: 15px; text-align: right; border-left: none; border-right: 1px ;"|40<br>0
|style="padding: 2px; width: 136px; text-align: left ; border-left: 1px ; border-right: none;"|39'''Base'''<br>23
|style="padding: 2px; width: 16px; text-align: right; border-left: none; border-right: 1px ;"|32<br>16
|-
|!colspan=5 style="padding: 2px; width: 136px; text-align: left ; border-left: 1px ; border-right: none;"|'''Base'''<br>31
|!style="padding: 2px; width: 15px; text-align: right; border-left: none; border-right: 1px ;"|<br>2416
|!colspan=3 style="padding: 2px; width: 56px; text-align: left ; border-left: 1px ; border-right: none;"|'''Flags'''<br>315
|!style="padding: 2px; width: 15px; text-align: right; border-left: none; border-right: 1px ;"|<br>0
|style="padding: 2px; width: 56px; text-align: left ; border-left: 1px ; border-right: none;"|'''Limit'''<br>19
|style="padding: 2px; width: 15px; text-align: right; border-left: none; border-right: 1px ;"|<br>16
|style="padding: 2px; width: 136px; text-align: left ; border-left: 1px ; border-right: none;"|'''Access Byte'''<br>7
|style="padding: 2px; width: 15px; text-align: right; border-left: none; border-right: 1px ;"|<br>0
|style="padding: 2px; width: 136px; text-align: left ; border-left: 1px ; border-right: none;"|'''Base'''<br>23
|style="padding: 2px; width: 16px; text-align: right; border-left: none; border-right: 1px ;"|<br>16
|}
{| class="wikitable" style="border-width: 3px; width: 640px;"
|-
|style="padding: 2px; width: 296px; border-right: none;" |31
|style="padding: 2px; width: 15px; text-align: right; border-left: none;" |16
|style="padding: 2px; width: 296px; border-right: none;" |15
|style="padding: 2px; width: 16px; text-align: right; border-left: none;" |0
|-
|colspan=5 style="padding: 2px; width: 296px; border-right: none;" |'''Base'''<br>15
|style="padding: 2px; width: 15px; text-align: right; border-left: none;" |<br>0
|colspan=3 style="padding: 2px; width: 296px; border-right: none;" |'''Limit'''<br>15
|style="padding: 2px; width: 16px; text-align: right; border-left: none;" |<br>0
|}