NASM 2.05 based x86 Instruction Reference[ch161]
A.5.140 LOADALL, LOADALL286: Load Processor State LOADALL ; 0F 07 [386,UNDOC] LOADALL286 ; 0F 05 [286,UNDOC] This instruction, in its two different-opcode forms, is apparently supported on most 286 processors, some 386 and possibly some 486. The opcode differs between the 286 and the 386. The function of the instruction is to load all information relating to the state of the processor out of a block of memory: on the 286, this block is located implicitly at absolute address 0x800, and on the 386 and 486 it is at [ES:EDI].