Hi!

While running RIPLinux* 6.3, I got the below oops.

What I did was boot up riplinux from USB key, start X, the run "reboot -f" on VT2.

* - http://www.tux.org/pub/people/kent-robotti/looplinux/rip/

After the oops I run "reboot" again and got the same oops again.
Note: I am not sure if I ran the 32 or 64 bit kernel.

For kernel config and (3 smallish) patches see:
http://www.tux.org/pub/people/kent-robotti/looplinux/rip/docs/kernel.txt
(or http://www.tux.org/pub/people/kent-robotti/looplinux/rip/docs/kernel64.txt)


HW: Asus P5K-E WiFi maonboard, BIOS version 1013
(Intel P35/ICH9R), CPU: Intel Core2 Q6600

The oops (both):

md: stopping all md devices.
BUG: unable to handle kernel NULL pointer dereference at 00000004
IP: [<c030b110>] device_shutdown+0x39/0x4c
*pde = 00000000 
Oops: 0000 [#1] 
Modules linked in: snd_mixer_oss snd_hda_intel snd_pcm snd_timer snd_page_alloc snd_hwdep snd
soundcore rtl8187 eeprom_93cx6

Pid: 1982, comm: reboot Not tainted (2.6.26 #8)
EIP: 0060:[<c030b110>] EFLAGS: 00010246 CPU: 0
EIP is at device_shutdown+0x39/0x4c
EAX: 00000000 EBX: ffffff90 ECX: 00000000 EDX: ffffff90
ESI: 28121969 EDI: b7fb2ff4 EBP: f7d0c000 ESP: f7d0de98
 DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068
Process reboot (pid: 1982, ti=f7d0c000 task=f3052740 task.ti=f7d0c000)
Stack: 00000000 c011e1bd c011e2ad 01234567 c011e3ec f7d0df14 f7d0df3c 0000002b 
       f28d552c c0149ba1 f28d55c8 c0150d11 ffffff9c ffffff9c 00000401 ffffff9c 
       f28d552c c0949308 00000001 f30528a4 f3052768 c0111cc7 c0111bc9 f30d6ac8 
Call Trace:
 [<c011e1bd>] kernel_restart_prepare+0x20/0x25
 [<c011e2ad>] kernel_restart+0x8/0x2e
 [<c011e3ec>] sys_reboot+0x112/0x14f
 [<c0149ba1>] put_filp+0x14/0x31
 [<c0150d11>] __path_lookup_intent_open+0x6a/0x72
 [<c0111cc7>] dequeue_entity+0xf/0x8d
 [<c0111bc9>] __dequeue_entity+0x1f/0x71
 [<c0111c2c>] set_next_entity+0x11/0x38
 [<c065eb56>] schedule+0x22e/0x24a
 [<c01241d1>] hrtimer_cancel+0xa/0x14
 [<c065f085>] do_nanosleep+0x4e/0x7b
 ...
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Try to rmmod all modules and see whether reboot works, if it is try to
unload only half of them, etc... (And tell us which module blocks your reboot)

If it will be hard to reproduce or procedure above won't work, please
enable "Kernel debugging" (CONFIG_DEBUG_KERNEL), "Driver Core verbose
debug messages" (CONFIG_DEBUG_DRIVER) and copy messages from dmesg which
happen before oops.


Marcin
--

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I managed to reproduce the problem. But it is not "exact science".
What I did was:
 - boot RIPLinux 6.3 USB stick
 - in boot menu select first option (boot 32 bit kernel)
 - when asked opt for keyboard selection
 - select "Slovene"
 - login as root on VT1
 - enter startx
 - in X right click and select XTerm in menu
 - in same menu select Setup/<fist option> (for wired network)
 - wait for the DHCP dialog to appear and click OK
 - from right click menu select Firefox/Start
 - ctrl-alt-f2 to VT2
 - login as root
 - enter: reboot -f

It gives the oops in 75% of cases.
The steps above do not load any modules that are not loaded by default anyway.

I attach the full dmesg output.

Regards,
David
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