[syslinux] Booting problem with memdisk + Thinkpad + USB

[Jan Ploski]

Hi,

I encountered a booting problem with memdisk 2.83, USB and IBM Thinkpad 
T61, apparently the same issue as described here:

http://syslinux.zytor.com/archives/2008-April/009850.html

The boot process always stops after "Loading boot sector... booting...". 
With debug tracers enabled, the last few output lines are:

Loading boot sector... FR<p>Dbooting...
FR<p>DFR<p>DFR<p>DFR<p>DFR<p>DFR<p><DFR<p>DFR<p>DFR<p>DFR<p>DFR<p>DFR<p>DFR<p>DFR
<p>DFR<p>DFR<p>DFR<p>DFR<p>DFR<p>DFR<p>DFR<p>DFR<p>DFR<p>DFR<p>DFR<p>DFGDFIDFD

A friend who uses memdisk more frequently also reported seeing the same 
symptoms (hanging after "Loading boot sector...") with desktops and even 
when booting from CDs.

I can see in source code that the 'I' tracer is output when the 
Invalid_jump branch is taken. Simply commenting out the jump instruction 
didn't fix the problem. Also, I didn't manage to capture the tracer 
output for comparison on another (Dell) notebook where memdisk works 
just fine using the same image because it disappeared from the screen 
too quickly.

Regards,
Jan Ploski