[ltp] Re: [gmane.linux.hardware.thinkpad] Re: T60p officially supported with SuSE SLED 10 by Levono

[David Abrahams]

Andrew Barr <andrew.james.barr@gmail.com> writes:

> (Restoring the CC to the list, hope you don't mind)

Not at all!

> On Wed, 2006-08-16 at 17:44 -0400, David Abrahams wrote:
>> Andrew,
>> 
>> My posts don't seem to be showing up on the list, so here's the
>> result.
>> 
>> How do I undo this stuff?  My sensors showed the GPU at 77 celsius
>> while idling, which is higher than I've ever seen before, and the fan
>> was running slower than it ever runs after being on for a few minutes
>> in Linux.  The whole machine felt really hot.  It's off now, needless
>> to say.
>
> Well, we don't know what the batinfo module does, it's binary-only, but
> to remove it, you need to 'modprobe -r batinfo', ideally delete the .ko
> file so it doesn't get autoloaded somehow again on boot, and probably
> reboot.

OK.

> That's if you extracted the .ko file manually. 

Ubuntu, so yes.

> If you're on SuSE, you
> need to remove the RPM files you installed using the 'rpm' command line
> tool or distro GUI tools.
>
> I assume your graphics hardware is a Radeon chip. You're better off
> asking other people about that GPU specifically. I don't know anything
> about them.
>
>> email message attachment
>
>> > plain text document attachment (dmesgs.txt)
>> > [17183159.440000] batinfo: no version for "struct_module" found: kernel tainted.
>> > [17183159.440000] batinfo: no version magic, tainting kernel.
>
> Well, maybe we need someone with SLED 10.1 or whatever it is, if that's
> all that was output.

I'm on a fresh install, so I'd be happy to install SLED just to find
out.

>> > Since I'm unable to distinguish what's interesting, I've attached a
>> > diff of "ls -lR1 /proc" before and after (see bottom).
>
>> > Does NHC undervolt the CPU without any special configuration?  It
>> > looked like that section of the NHC panel was not enabled (I'd have
>> > had to check a box).  
>
> I don't know. Anyone have NHC experience care to chime in?
>
>> > I just turned NHC on and the machine cooled off
>> > a little and the fan stopped, like magic.
>
> Well, just remember it's not magic. 

Of course not.

> I think people forget that sometimes when they are having issues
> with Linux that don't show up in Windows. I don't know exactly what
> that program does, it certainly doesn't do anything that Linux (or
> other OSes, for that matter) cannot do. It's a matter of figuring
> out what that program does and reproducing it in Linux, or (in a
> worst-case scenario) finding out why that would not be entirely
> possible.

Yes.  I'm sure the author would be forthcoming.

> I played around with the undervolting patch available at
> http://linux-phc.sourceforge.net/ , and after finding some reasonable
> values, my machine idles at about 43C if the fan cools it and can go as
> low as 41. As long it it is idling or just lightly loaded, you can shut
> off the fan and it will stay there. And I haven't even tested battery
> life yet. There's also some patches out there that let you take over fan
> policy from the firmware. Some people seem to think that the IBM
> defaults for shutting off the fan are too low--the fan never goes off.
> That has certainly been my experience--even at 41C the fan stayed
> on.

That was my experience with my Dell inspiron 9300 also;  I installed
i8kFanGui and it's comfortable at around 44 centigrade.

> Look at ThinkWiki on the fan control pages, there are some fan control
> scripts (userspace daemon) and also a patch that creates a kernel thread
> to control the fan--this is for the paranoid who don't trust user space
> to be reliable. Be forewarned, the patches, especially the kernelspace
> daemon one, are somewhat out of date and require merging into recent
> kernels by hand.

So far I've been able to avoid re-learning how to build kernels, but
it looks like that trip is over.

> OTOH, the fan control scripts may not require any patching at all.

I think that's right.

>> > And what is it about Windows that allows undervolting to be done
>> > without patching the kernel (or, what is it about Linux that requires
>> > a kernel patch?)
>
> You may be patching the kernel when you install NHC, in a manner of
> speaking. If it installs any drivers (.sys files) then it is doing the
> equivalent of patching Windows' kernel.

That's more like installing a new kernel module, innit?  A kernel
patch requires recompilation, IIUC.

>> > plain text document attachment (procdiffs.txt)
> [snip]
>
> Hm, nothing I haven't seen in a regular system.
>
> (The list was huge, BTW, and might be why your posts aren't showing
> up--the message was too big. So, if anyone wants to see it resend it to
> them as a gzipped attachment)

Except that I posted something much shorter about an hour before that
I never saw either.  It was just that business above about kernel
patching, mostly.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com