SELECTOR -> LDTR
LDTR is loaded by LLDT. The operand (word) contains a selector to a local GDT (Global Descriptor Table). The descriptor registers are not affected.The task state segment LDT field does not change.
The LDTR is marked invalid if the selector operand is 0. A #GP fault is caused by all descriptor references (except LSL VERR, VERW, or LAR instructions).
LLDT is not used in application programs. It is used in operating systems.
Load the LLDT register from the effective address (addressed by the EBX register plus and offset of 5):