[syslinux] some issues with modules/syslinux

[Bernd Blaauw]

Dear Syslinux bootloader list,

I'm running into a few issues concerning Syslinux modules here, hoping 
you can answer one or more of the following questions:

* Where's "ifmemdsk.c32" ? 4.05, 4.06pre1 and latest 4.10pre seem to 
lack it. Only the "ifmemdsk.c" file, which is likely sourcecode. Not 
seeing any "ifmemdsk.cbt" legacy comboot module.

* Do COM32 modules have their own memory requirements? Menu.c32 fails on 
a 2MB QEMU system, same for CHAIN.C32, yet Isolinux (and Syslinux) load 
fine if no com32 is loaded. Memdisk also loads fine (only tested with 
360K floppy image).
I haven't tried 1MB QEMU (hangs on win32 due to either QEMU or SeaBIOS 
or bug) nor 0MB system (Coreboot with Cache-As-Ram in theory).

* There doesn't seem to be a fallback to text-only mode for the UI 
parameter in case of low memory situations. Physical systems have 4MB 
already at the very least, but loading an ISO into RAM followed by 
booting it can get you into situations where there's just enough memory 
to load isolinux.bin/cfg but not any COM32 module, thus also not GUI. 
Thus, hang. (and, relying on localboot 0x00/0x80 instead of CHAIN.C32).
Trying with 3MB or more seemed to work just fine

* is there a working version of memdisk.c32 [http://reboot.pro/14468/] ?
COM32 modules seem to be version-dependant and trying this with 4.05 
ended up with "not a COM32R image" so I guess it's written for 4.04.

* How's Syslinux influencing gate A20? And MEMDISK? They both seem to 
result in different A20 access methods being displayed by various memory 
managers under FreeDOS. One of them actually manages to crash unfortunately.

My apologies for the many questions in a single email. Thanks also for 
having brought up the (slightly outdated) Syslinux website.
[ http://www.syslinux.org/wiki/index.php/The_Syslinux_Project ]

with best regards,

Bernd Blaauw