it is denied. is can be elaborated this way – a call gate with a DPL of 2 can be used by a pro-
gram with CPL 2 to access a system service at level 0 – but the same gate cannot be used by a
program with a CPL of 3. Figure 15.24 shows a call gate.
How to Use Call Gates?
e instruction Call xxxxx may be used where xxxxx may be specifi ed as a gate name, but usually
generates a selector leading us to an entry in the GDT or LDT, where the gate is stored. In the
call gate, the detail of the target code segment is available and using this, the calling program
enters the code segment at a higher privilege, but only at the ...
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