nc4200 that doesn't reboot

[hamradio]

Hi,

I have an HP-Compaq NC4200 notebook (Pentium 4 M, ICH6 chipset, i915 graphic chip, etc.) running Debian Lenny.

This system can only shutdown, and not reboot.

If I do "shutdown -r now" it terminates regularly all processes but it ends up with:

Restarting system.
machine restart

and at this point it hangs on until I manually power it off with the power switch.

The sysrq "alt-stamp-b" has no effect.

This happens with my 2.6.27.4 custom "vanilla" kernel as well as with the official 2.6.26-1-686 Debian kernel.

Somewhere on the net I've read that some modules could prevent the system from switching off, so I've tried going down at runlevel 1, then killing all (killable) processes, and "modprobe -r" all modules, reaching this situation:

# lsmod
Module Size Used by
ipv6 242788 8
processor 27824 1
thermal_sys 10976 1 processor
hwmon 2196 1 thermal_sys
intel_agp 25476 1
agpgart 28656 1 intel_agp

# ps ax
PID TTY STAT TIME COMMAND
1 ? Ss 0:00 init [S]
2 ? S< 0:00 [kthreadd]
3 ? S< 0:00 [ksoftirqd/0]
4 ? S< 0:00 [rcu_sched_grace]
5 ? S< 0:00 [events/0]
6 ? S< 0:00 [khelper]
35 ? S< 0:00 [kintegrityd/0]
37 ? S< 0:00 [kblockd/0]
39 ? S< 0:00 [kacpid]
40 ? S< 0:00 [kacpi_notify]
143 ? S< 0:00 [ata/0]
144 ? S< 0:00 [ata_aux]
146 ? S< 0:00 [kseriod]
177 ? S 0:00 [pdflush]
178 ? S 0:00 [pdflush]
179 ? S< 0:00 [kswapd0]
223 ? S< 0:00 [aio/0]
316 ? S< 0:00 [scsi_eh_0]
319 ? S< 0:00 [scsi_eh_1]
352 ? S< 0:00 [kjournald]
6269 tty1 Ss 0:00 init [S]
6270 tty1 R 0:01 bash
7479 tty1 R+ 0:00 ps ax

But the command "shutdown -r now" failed again, remaining stuck always at same point...

The bios and the hardware should be fine, as the system can regularly reboot under Windoze XP.

Anyone could please give me some hints?

Thank you in advance.

[Ivan Ferreira · Accepted solution]

Please see the Matti Kurkela answer here:

http://forums13.itrc.hp.com/service/forums/questionanswer.do?admit=109447627+1227034179005+28353475&threadId=1181278

[hamradio]

Hi Ivan,

the post you directed me has solved the problem.

I simply had to append "reboot=b" to the kernel command line into /etc/lilo.conf.

Thank you very much.