Eric W. Biederman
ebiederman at lnxi.com
Sun Mar 14 00:20:01 CET 2004
ron minnich <rminnich at lanl.gov> writes:
> On Sat, 13 Mar 2004, Takeshi Sone wrote:
> > Some OSs call 16-bit BIOS services in VM86 mode.
> > In that case you can't switch to 32-bit mode by yourself.
> how about we list those OSes, see if they can be fixed, or if we don't
> what does windows do?
VM86 mode... At least the windows 9x kernel. NT?
The important point to note is that gas has a directive ``.code16gcc''
which directs gas to assemble 32bit code that runs in 16bit mode and
in vm86 mode. So if we can fit everything in 256K we are fine.
So when doing a rewrite of rombios.c that is readable we should try
that. 256K is a little tight I admit but if we don't go beyond simple
standard features it is enough.
The fundamental point here is that you can write 32bit code that
will run in VM86 mode.
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