IIRC there were huge swathes of 'gotchas' with running 286 pmode code in 386 pmode, to the point where lots of code simply wouldn't work at all. (One thing tha

IIRC there were huge swathes of 'gotchas' with running 286 pmode code in 386 pmode, to the point where lots of code simply wouldn't work at all. (One thing that springs to mind was that the way addresses running past the end of a segment worked was different)