Lm-sensors in Maverick shows CPU core Temperatures too high

[jolo]

Lm-sensors in Maverick shows the core temperatures about ten degrees higher than in Lucid on my Lenovo ThinkPad R61i 8932GMG. With both CPU cores 1 Ghz (50%) ondemand. CPU fan about 3000 RPM.

Ubuntu Maverick Terminal outputs

jolo@R61i:~$ sensors

coretemp-isa-0000
Adapter: ISA adapter
Core 0: +52.0°C (high = +100.0°C, crit = +100.0°C)

coretemp-isa-0001
Adapter: ISA adapter
Core 1: +51.0°C (high = +100.0°C, crit = +100.0°C)

jolo@R61i:~$ acpi -t
Thermal 0: ok, 37.0 degrees C
Thermal 1: ok, 45.0 degrees C

Ubuntu Lucid Terminal outputs

jolo@R61i:~$ sensors

coretemp-isa-0000
Adapter: ISA adapter
Core 0: +36.0°C (high = +85.0°C, crit = +85.0°C)

coretemp-isa-0001
Adapter: ISA adapter
Core 1: +33.0°C (high = +85.0°C, crit = +85.0°C)

jolo@R61i:~$ acpi -t
Thermal 0: ok, 36.0 degrees C
Thermal 1: ok, 43.0 degrees C

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: lm-sensors 1:3.1.2-6
ProcVersionSignature: Ubuntu 2.6.35-8.13-generic 2.6.35-rc5
Uname: Linux 2.6.35-8-generic i686
Architecture: i386
Date: Sat Jul 17 21:17:13 2010
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Alpha i386 (20100630.2)
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
SourcePackage: lm-sensors-3

[akatdim (akatdim)]

For me this bug correct only on kernel version 2.6.35 .

TOSHIBA Satellite A200 (laptop)
Board: TOSHIBA ISKAA

CPU(Intel Centrino):
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
CPU(s): 2
Thread(s) per core: 1
Core(s) per socket: 2
CPU socket(s): 1
NUMA node(s): 1
Vendor ID: GenuineIntel
CPU family: 6
Model: 15
Stepping: 13
CPU MHz: 1000.000
L1d cache: 32K
L1i cache: 32K
L2 cache: 2048K

Package: lm-sensors, version: 1:3.1.2-6
Kernel: 2.6.35-14-generic
OS: Ubuntu maverick (development branch) 10.10

[shuelee (shuelee2000)]

Hi,

I have a same problem wtih kernel 2.6.35 of Maverick. temperatures are 65°C and 69°C

With kernel 2.6.32-25 in Maverick, temperatures are 39°C and 43°C.

My laptop : Toshiba A300 and intel core 2duo T5750

Excuse for my english :)

[Balaji (balaji-ramasubramanian)]

I confirm this bug. The same is with me. In fact at the time of upgrade from Lucid Lynx, the upgrade for the Toshiba temperature sensor driver fails. I believe the sensors for the core temperature modules are also failing.

Another thing is that while Ubuntu has made significant progress in making the clean installation from CD very seamless and easy, the same is not true for upgrades. It is full of a variety of bugs. This needs a serious change in future releases.

For the sensors here is my output:

$ sensors
acpitz-virtual-0
Adapter: Virtual device
temp1: +48.0°C

coretemp-isa-0000
Adapter: ISA adapter
Core 0: +59.0°C (high = +100.0°C, crit = +100.0°C)

coretemp-isa-0001
Adapter: ISA adapter
Core 1: +59.0°C (high = +100.0°C, crit = +100.0°C)

I have never kept the laptop above 45 deg C.

[gmcd (gmcd)]

I can confirm this bug, too. On my laptop FS Esprimo M9400 I have temp on both of my cores about 75 - 80 C. However, fan is OK. In comparison with lucid, I have temp about 55 - 60C. So, I think that my lm-sensors are showing temp about 20C higher than it's in real.

kernel 2.6.35-22-generic #33-Ubuntu SMP Sun Sep 19 20:32:27 UTC 2010 x86_64 GNU/Linux

Distributor ID: Ubuntu
Description: Ubuntu 10.10
Release: 10.10
Codename: maverick

Thanks for responds.
John

[Mark Dillavou (line72)]

I too can confirm this bug. On my laptop, Dell Latitude D620, I have a temp on both cores of 61C, and cannot seem to get it lower than that. My fans also continously run a full speed.

kernel 2.6.35-22-generic #33-Ubuntu SMP Sun Sep 19 20:34:50 UTC 2010 i686 GNU/Linux

Distributor ID: Ubuntu
Description: Ubuntu 10.10
Release: 10.10
Codename: maverick

I also had problems under Lucid. I hoped upgrading to Maverick would help, but so far has not. Karmic always worked well for me.

Thanks,
Marcus

[gmcd (gmcd)]

I've downgraded kernel to 2.6.32-0206322410-generic #201010060909 SMP Wed Oct 6 09:11:07 UTC 2010 x86_64 GNU/Linux, which I've downloaded from kernel.ubuntu.com and my temp is working well.

So, it seems to be rather kernel bug, than lm-sensors bug. Maybe it would be to fill the bugreport to some kernel bugtracker, wouldn't be?

Linux 2.6.32-0206322410-generic #201010060909 SMP Wed Oct 6 09:11:07 UTC 2010 x86_64 GNU/Linux

Distributor ID: Ubuntu
Description: Ubuntu 10.10
Release: 10.10
Codename: maverick

Thanks, John

[Balaji (balaji-ramasubramanian)]

I think I found a solution:

I found that if we instead use the 2.6.32-25-generic kernel released with Ubuntu 10.04, the sensors work fine. They don't work on Maverick's 2.6.35-22-generic kernel. So the bug should be on the kernel. I am guessing this should affect the new kernel 2.6.35 releases on Gentoo and other Linux distros too. Please confirm and add a major bug on the kernel.

For the moment, the solution I have is to use the older kernel image. Any other better solutions welcome.

[Balaji (balaji-ramasubramanian)]

Update: an update for kernel 2.6.35-22 is available for Maverick. I don't know if this bug is fixed in it.

[Balaji (balaji-ramasubramanian)]

Some other bugs were duplicates of this one. So I've marked them as duplicates of this one. This is a clear bug that affects many. Please mark the importance high for this bug and fix it. The guess is that it is a problem with the Maverick released 2.6.35-22 kernel.

[gmcd (gmcd)]

Hello, I've tested the new version of kernel 2.6.35-22, which ships through update manager in Maverick.
However, the bug still remains.

[Mark Dillavou (line72)]

I've also downgraded, but I downgraded to kernel 2.6.31-02063113-generic #02063113 SMP Fri Jun 4 19:02:37 UTC 2010 i686 GNU/Linux, and everything is working much better! Not only is my temperature cooler, but my load stays low, unlike the maverick kernel where my load hovered close to 1.0!

[gmcd (gmcd)]

After little testing for last couple of days, I've discovered that on my system maverick kernel show CPU temperature about 20 degrees of Celsius higher, than with lucid or any older kernels.

[Michael Terry (mterry)]

See this blog post: http://smackerelofopinion.blogspot.com/2010/09/sensors-reporting-hot-cpu-in-maverick.html

The takeaway is that it may be nothing. See if the output of:

cat /sys/devices/platform/coretemp*/temp1_crit

has changed from 10.04 to 10.10. If so, it's probably just noise and isn't actually running hotter.