-=> On 08-09-22 12:10, Digital Man wrote to Tony Langdon <=-
DM> Unfortunately, no. 64-bit x86 processors, when operating in "long mode"
DM> (64-bit mode) do not support the "virtual 86" mode that they have in
DM> 32-bit mode. --
While not "virtual 8086 mode" as we've known it, from
https://en.wikipedia.org/wiki/Virtual_8086_mode#64-bit_and_VMX_support
"Virtual 8086 mode is not available in x86-64 long mode, although it is still
present on x86-64 capable processors running in legacy mode.
Intel VT-x brings back the ability to run virtual 8086 mode from x86-64 long
mode, but it has to be done by transitioning the (physical) processor to VMX
root mode and launching a logical (virtual) processor itself running in virtual
8086 mode.[14]
Westmere and later Intel processors usually[15] can start the virtual processor
directly in real mode using the "unrestricted guest" feature (which itself
requires Extended Page Tables); this method removes the need to resort to the
nested virtual 8086 mode simply to run the legacy BIOS for booting.[16][17]
AMD-V can do virtual 8086 mode in guests, too, but it can also just run the
guest in "paged real mode" using the following steps: you create a SVM (Secure
Virtual Machine) mode guest with CR0.PE=0, but CR0.PG=1 (that is, with
protected mode disabled but paging enabled), which is ordinarily impossible,
but is allowed for SVM guests if the host intercepts page faults.[18] "
... Bit: The increment by which programmers slowly go mad
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