Programs such as the pre-XMS versions of RAMDRIVE.SYS (1985),[3][1][4] SMARTDRV.SYS (1986)[4] as well as HIMEM.SYS (2.03, 1988-08-04; 2.04, 1988-08-17)[4] drivers in MS-DOS, Uniform Software Systems' The Extender (1985) and The Connector (1985) for Lotus 1-2-3, Above Disk (1986)[5] (a LIMulator by Above Software (formerly Tele-Ware West aka Los Angeles Securities Group) that converted hard disk space or extended memory into expanded memory), and OS/2 1.0[3][1] and 1.1[6] used the 286 LOADALL instruction.
Another interesting usage of LOADALL, laid out in the book The Design of OS/2,[9] would have been to allow running former real-mode programs in 16-bit protected mode, as utilized by Digital Research's Concurrent DOS 286 since 1985,[10][11][12] as well as FlexOS 286[13] and IBM 4680 OS[14][15] since 1986.
Marking all the descriptor caches in the GDT and LDTs "not present" would allow the operating system to trap segment-register reloads, as well as attempts at performing real-mode–specific "segment arithmetic" and emulate the desired behavior by updating the segment descriptors (LOADALL again).
Nevertheless, the idea was not lost; it led Intel to introduce the virtual 8086 mode of the 80386, allowing the implementation of "DOS boxes" at last in a relatively efficient and documented way.
On Intel 80386, asserting the undocumented pin at location B6 causes the microprocessor to halt execution and enter ICE mode.
In SMM, the RSM instruction is used to load a full CPU state from a memory area.
The 80286 LOADALL instruction can not be used to switch from protected back to real mode[19] (it can't clear the PE bit in the MSW).