[Info-vax] Intel proposal to simplify x86-64

[David Wade]

On 05/06/2023 02:02, Arne Vajhøj wrote:
> On 6/4/2023 3:31 PM, John Dallman wrote:
>> In article <630361da-4c95-4556-b7a6-40cc74829383n at googlegroups.com>,
>> n.rieck at bell.net (Neil Rieck) wrote:
>>> As far as the Intel proposal is concerned, "I thought" that
>>> Microsoft has already blocked running 16-bit programs on their
>>> 64-bit OS for a few years now.
>>
>> They deliberately left it out of 64-bit Windows from the beginning of
>> that OS. The hardware has been capable of running 16-bit code since AMD
>> first designed x86-64, but Microsoft only exploited that in 32-bit
>> Windows.
> 
> Are you sure that was a MS choice?
> 
> 16 bit programs are a AFAIK not run in "real mode"
> but in "virtual 8086 mode".
> 
> And based on what I can read then "virtual 8086 mode"
> is only available when the system is running in
> "32 bit mode" / "protected mode" / "legacy mode" and
> not when running in "64 bit mode" / "long mode".
> 
> Arne
> 
> 
> 
I think it was more complexity. There is a version of wine that allows it:-

https://github.com/otya128/winevdm

and I thought wine did not contain a CPU emulator, but looking at the 
readme.md perhaps I am wrong...

Dave