[syslinux] Possible memdisk bug

Quinn plattel at tiscali.dk
Mon May 9 12:58:58 PDT 2005

Hello everyone,

I am trying to identify a bug in memdisk with regards to booting memdisk 
images from a usb pen/flash disk. Can anyone try and download the 
following two images and zcat/dd them to a usb pen/flash disk:

Use the following command in linux to extract the images to the usb 
pen/flash disk under linux:

zcat image.gz|dd of=/dev/sda

...would gunzip image.gz raw to the usb pen/flash disk at address /dev/sda.

Then boot the usb pen/flash disk from a computer that supports booting 
from a hdd-type usb pen/flash disk.  What I would like to know is which 
bioses the syslinux image fails on.  Remember when syslinux boots, try  
to boot both the dft and freedos entries in the syslinux boot screen.  
If dft goes into the drive test program and freedos boots to the A: 
prompt, then the test succeeded.  The fdos image should work no matter 
what - memdisk is not involved here.

I would like to know the results from any bios that supports booting 
from usb devices.  I have tested so far under recent AMI and IBM bioses 
- AMI seems to work without problems, but IBM bioses do not.

If possible, try and test with and without an internal hard disk 
installed and enabled in the bios.  I have discovered memdisk images 
works a lot of the time without a internal hard disk but fails when a 
internal hard disk is installed and enabled in the bios.

When you report back your results - post it on this thread - thanks!


References: The freedos images was created via the FreeDos project - 
www.freedos.org ; The dft image was downloaded here: 

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