Re: Linux 2.6.25 (coretemp reads high temperatures)

[Kasper Sandberg <lkml@metanurb.dk>]

On Wed, 2008-04-23 at 11:43 +0300, Maxim Levitsky wrote:
> On Saturday, 19 April 2008 04:51:48 Len Brown wrote:
> > On Friday 18 April 2008, Matthew wrote:
> > > Hi everyone, hi Linus,
> > > 
> > > congratulations on this new great kernel-release :)
> > > 
> > > I've another "regression" to report for 2.6.25:
> > > 
> > > it's concerning much higher temperatures being read out by the
> > > "coretemp" kernel-module in comparison to 2.6.24* series
> > > 
> > > e.g. where temperatures were around 40-47°C they are now constantly
> > > jumping around 55-70°C (even in idle !)
> 
> I just updated from 2.6.24 to 2.6.25
> (I usually follow whole development cycle, but I was very busy, so I skipped 2.6.25 cycle)
> 
> I confirm this.
> I *know* that temperatures reported now are wrong.

I too can confirm that it reports incorrect temperatures.

I have a Q9450, and this is my "sensors" output:
it8718-isa-0290
Adapter: ISA adapter
<snip>
temp1:       +44°C  (low  =  +127°C, high =  +127°C)   sensor =
thermistor
temp2:       +22°C  (low  =  +127°C, high =   +60°C)   sensor = diode
temp3:        -2°C  (low  =  +127°C, high =  +127°C)   sensor =
thermistor
vid:      +0.000 V

coretemp-isa-0000
Adapter: ISA adapter
Core 0:      +44°C  (high =  +100°C)

coretemp-isa-0001
Adapter: ISA adapter
Core 1:      +44°C  (high =  +100°C)

coretemp-isa-0002
Adapter: ISA adapter
Core 2:      +43°C  (high =  +100°C)

coretemp-isa-0003
Adapter: ISA adapter
Core 3:      +41°C  (high =  +100°C)


temp2 is the cpu temperature(matches bios), temp1 is the northbridge(i
think, bios says "system temp").

i have watercooling, and well :P when i touch the "tube", its normal
room temperature, and believe me, i would notice if it was 45.. this is
with my cpu at idle - at full load on all 4 cores, temp2 says 35, and
~60 on coretemp, and THIS i would surely be able to notice over room
temp :)

any progress on this bug?

> 
> The reason is that bios did report same temperatures as coretemp in 2.6.24,
> moreover some time ago I have run a cpu tool (don't remember its name) on windows
> which similar to coretemp reads from each core directly, sensor data , 
> and I noticed that temperature that bios reports is exactly the average 
> temperature of both cores
> (I had to run this on windows - intel haven't released 
> drivers for their QST for temperature monitoring from bios - very sad)
> 
> And the driver did say in kernel log that TJMAX is 85C
> 
> Lets at least make a kernel option to override tjmax?
> 
> Best regards,
> 	Maxim Levitsky
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