[ltp] Hard lock on T42p

[Henrique de Moraes Holschuh]

On Sat, 30 May 2009, Mat Marcus wrote:
> On Sat, May 30, 2009 at 4:48 PM, Henrique de Moraes Holschuh
> <hmh@hmh.eng.br> wrote:
> > On Sat, 30 May 2009, Mat Marcus wrote:
> >> I had a similar problem with recent Ubuntu distributions on a T42p.
> >
> >  ...
> >
> >>   echo disabled > /proc/acpi/ibm/bluetooth
> >>
> >> was what finally allowed me to wake the machine without crashing.
> >
> > BIOS and EC version, please?  ThinkPad-acpi logs them when it is loaded .
> 
> Thanks for asking:
> 
> ThinkPad BIOS 1RETDRWW (3.23 ), EC 1RHT71WW-3.04

Urk.  It is the newest.

Ok, let's see if it is thinkpad-acpi that's causing this.  I have code
in there to store bluetooth state to NVRAM before suspend and shutdown,
and it is relatively new.

I am sure I am not doing anything weird on that code, but firmware bugs
would be nothing new, so it might be a bad idea on a T42 while it works
perfectly well on newer ThinkPads.

I will need help here, I know it is a major hassle to reset the CMOS,
but without help from someone with a T42 that suffers this problem, I
won't be able to do anything about it.

So, if you would be willing to risk messing your NVRAM again, please
test a 2.6.29 Mainline kernel, and see if it causes the problem.  Here's
a Ubuntu page on how to use a Mainline kernel with Ubuntu, the Ubuntu
way:

https://wiki.ubuntu.com/KernelMainlineBuilds

If you can reproduce the problem with the mainline 2.6.29 kernel, please
do this:

Find this function in the kernel source, on file
drivers/laptop/x86/thinkpad-acpi.c:

static void bluetooth_suspend(pm_message_t state)
{
	some stuff
}

and make it empty like this:

static void bluetooth_suspend(pm_message_t state)
{
}

Do the same for the function bluetooth_shutdown, in the same file.

Now, recompile the kernel (or just the thinkpad-acpi module), and use the
new one.

Can you still reproduce the problem after you do that?

-- 
  "One disk to rule them all, One disk to find them. One disk to bring
  them all and in the darkness grind them. In the Land of Redmond
  where the shadows lie." -- The Silicon Valley Tarot
  Henrique Holschuh