The IDT may contain any of three kinds of descriptor:
- Task gates - Interrupt gates - Trap gatesFigure 9-3 illustrates the format of task gates and 80386 interrupt gates and trap gates. (The task gate in an IDT is the same as the task gate already discussed in Chapter 7.)
80386 TASK GATE
31 23 15 7 0
+-----------------+-----------------+---+---+---------+-----------------+
|#############(NOT USED)############| P |DPL|0 0 1 0 1|###(NOT USED)####|4
|-----------------------------------+---+---+---------+-----------------|
| SELECTOR |#############(NOT USED)############|0
+-----------------+-----------------+-----------------+-----------------+
80386 INTERRUPT GATE
31 23 15 7 0
+-----------------+-----------------+---+---+---------+-----+-----------+
| OFFSET 31..16 | P |DPL|0 1 1 1 0|0 0 0|(NOT USED) |4
|-----------------------------------+---+---+---------+-----+-----------|
| SELECTOR | OFFSET 15..0 |0
+-----------------+-----------------+-----------------+-----------------+
80386 TRAP GATE
31 23 15 7 0
+-----------------+-----------------+---+---+---------+-----+-----------+
| OFFSET 31..16 | P |DPL|0 1 1 1 1|0 0 0|(NOT USED) |4
|-----------------------------------+---+---+---------+-----+-----------|
| SELECTOR | OFFSET 15..0 |0
+-----------------+-----------------+-----------------+-----------------+