Re: booting Linux from a dos box in win3.1

Hans Lermen (lermen@elserv.ffm.fgan.de)
Tue, 3 Sep 1996 10:24:26 +0200 (MET DST)


On Mon, 2 Sep 1996, 0xdeadbeef wrote:

> ... basically, i need to know
> if it's at all possible to boot Linux from a Windows 3.1 DOS box without
> exiting Windows.

Without 'exiting Windows': NO !

The DOS-Box runs in VM86 mode, out of this you can't enter neither
'_real_ realmode' nor 'ring0 protected mode'. Loadlin can overcome this
restriction when a VCPI-Server is available: it first enters VCPI, then
returns to realmode, then jumps back to arch/i386/boot/setup.S code.
However, Windows (may be 3.1 or '95) don't supply a VCPI-Server,
so any attempt to enter ring0 protected mode will be refused.

>
> Another thing that would work (though this is really off-topic) would be
> a program runnable from a DOS box that would kick the computer back to
> DOS, in a stable enough state to use LOADLIN.

I have been told the following:

Under Windows'95 you can have a batch file containing a Loadlin
commandline. If you link this to a clickable icon and set the
properties to using native DOS, then clicking the icon will exit
Windows'95 and boot Linux.

Hans
<lermen@fgan.de>