On Wed, May 09, 2012 at 08:44:45PM -0400, Kevin O'Connor wrote:
> On Wed, May 09, 2012 at 08:57:53AM -0700, Alain Ribière wrote:
> > I wonder what is the CDOS system at 0D4000... It seems a bit strange.
>
> Very odd.  This is still controlled by seabios.  Indeed, if I apply
> this (clearly incorrect) patch to seabios:
>
> diff --git a/src/shadow.c b/src/shadow.c
> index c0c8cc2..73c0670 100644
> --- a/src/shadow.c
> +++ b/src/shadow.c
[...]

Just for kicks, I tried a simple hack to try and reserve more memory
in the c/d/e-segments, and it seems to work for the image you posted.
Run:

python -c 'import sys; sys.stdout.write("\x55\xaa\xc8\xcb\x6e" + "\x00"*(100*1024 - 5))' > dummy.rom

and then add "-option-rom dummy.rom" to your qemu command line.  (The
idea is to build a 100K dummy option rom that seabios will load and
mark as read-only memory.)

-Kevin