Xen users - Feb 2007 - Xen dom0 kernel freezes - how to debug it?

I wanted to use Xen 3.0.4 on a diskless server (started via PXE/tftp).

I use open-iscsi (2.0-754) to access the root filesystem etc.

Unfortunately, it doesn''t work very well - dom0 freezes after some
time,
even if I don''t start xend.

It''s very easy to freeze the machine with a simple script that uses
"dd"
command:

#!/bin/bash

FILE=/file.test

i=1

while true
do
echo "Run: $i"
dd if=/dev/zero of=$FILE bs=1k count=400000
free

i=$((i+1))
done


Usually, the machine will freeze after 5-7 runs.

The freeze doesn''t happen if I replace the kernel with a regular one 
(with no Xen patches).


"Freeze" characteristics:

- happens only with Xen kernel; no domUs are running; even xend was not 
started

- I can''t switch between consoles (ctrl+alt+F1 etc.) anymore

- I can ping the machine, and can establish a connection to ports that 
were already opened (like SSH/22) i.e. with telnet (the ports are open, 
and I can connect to them, but they do not respond)

- I can use magic SysRQ keys to reboot the machine


Is there a way to debug it?


-- 
Tomasz Chmielewski
http://wpkg.org

_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users