[SeaBIOS] SEABIOS and DOS compatibility

[Gerhard Wiesinger]

Hello,

I bisected down 2 DOS 6.22 compatibility issues:

1.) COMMAND.COM can not be loaded high, 
9c98517c938d20c38f537d516c71b30bb60c3ea0 is the first bad commit
Looks like and UMB generated which is not recognizeable ...
Before: 9E80-9F7F: 4k EBDA, 9F80-9FFF: 2k UNUSED, really unused or used 
for option ROMs?
After: 9F00-9FFF: 4k EBDA, now the 2k area is somewhere above and will 
be used by memory managers???

2.) 59d6ca52a7eba5b1f4f2becf70fd446dccaf0a2e is the first bad commit
Opening a file and closing a file raises a 386 exception

I'm using LSI 53C895A adapter with LSI BIOS and disabled LSI BIOS .

Any ideas?

Release are in the state:
git checkout rel-1.7.1 => NOT OK
git checkout rel-1.7.0 => OK

Thank you.

Ciao,
Gerhard