Booting virtual DOS floppies using GRUB

[Dr A V Le Blanc]

Long ago I wrote to this list asking for information about possibly
booting virtual DOS floppies using GRUB, and nothing came of it
at the time, though several people have written me asking whether
further developments have taken place.

Someone has pointed out to me that syslinux/pxelinux has a feature
called 'memdisk' which ought to do exactly what I want.  Memdisk
is treated by the bootloaders in that family as a kernel, and
the floppy image as an initrd; memdisk handles setting up the
initrd as a ramdisk and intercepting the BIOS's int 13 and int 15
calls where necessary.  Since memdisk looks rather like a Linux
kernel, it should be possible under GRUB to say

     kernel   (hd0,0)/memdisk
     initrd   (hd0,0)/dosfloppy_image

and to boot.  Unfortunately it doesn't work; it just hangs.
Given that this is much more specific than the original question,
what needs to change in GRUB to be able to use memdisk successfully?
Information about memdisk is available at http://syslinux.zytor.com/

     -- Owen
     address@hidden