Intel 253668-032US Benutzerhandbuch
7-12 Vol. 3
TASK MANAGEMENT
to be handled by handler tasks. When an interrupt or exception vector points to
a task gate, the processor switches to the specified task.
a task gate, the processor switches to the specified task.
Figure 7-7 illustrates how a task gate in an LDT, a task gate in the GDT, and a task
gate in the IDT can all point to the same task.
gate in the IDT can all point to the same task.
7.3 TASK
SWITCHING
The processor transfers execution to another task in one of four cases:
•
The current program, task, or procedure executes a JMP or CALL instruction to a
TSS descriptor in the GDT.
TSS descriptor in the GDT.
•
The current program, task, or procedure executes a JMP or CALL instruction to a
task-gate descriptor in the GDT or the current LDT.
task-gate descriptor in the GDT or the current LDT.
Figure 7-7. Task Gates Referencing the Same Task
LDT
Task Gate
TSS
GDT
TSS Descriptor
IDT
Task Gate
Task Gate