Syslog contains i2c failures

[h1d3m3]

May 14 14:30:35 hostname kernel: i2c i2c-0: SMBus Timeout!
May 14 14:30:35 hostname kernel: i2c i2c-0: Failed reset at end of transaction (01)
May 14 14:30:35 hostname kernel: i2c i2c-0: Failed! (01)
May 14 14:30:35 hostname kernel: i2c i2c-0: Failed! (01)
May 14 14:30:35 hostname kernel: i2c i2c-0: Failed! (01)

 

Curious what these messages are about as I am seeing a lot of them in syslog. I suspect it has something to do with a process trying to get fan/temperature readings and failing?

 

I have Dynamix System Temperature running with "k10temp nct6775 jc42" drivers on a ASRockRack X399D8A-2T w/ AMD Ryzen Threadripper 1900X on unRaid 6.9.2. Getting some temperature readings from the modules listed, though no fan speeds.

 

Not sure what is triggering the i2c failures (or what effect the failures are having, if anything at all).

 

Any thoughts/ideas welcome, thanks.

Edited May 15, 2021 by h1d3m3

[h1d3m3]

Well, this has turned from a annoying curiosity to an actual system stability issue.

 

Common problems is now reporting :

 

"Either your server has an extremely long uptime, or your syslog could be potentially being spammed with error messages. A reboot of your server will at least temporarily solve this problem, but ideally you should seek assistance in the forums."

 

And there are hundreds of thousands of these errors produced overnight:

 

May 17 16:38:36 secant kernel: i2c i2c-0: SMBus Timeout!
May 17 16:38:36 secant kernel: i2c i2c-0: Failed reset at end of transaction (01)

...

May 17 19:08:10 secant kernel: i2c i2c-0: Failed! (01)
May 17 19:08:10 secant kernel: i2c i2c-0: Failed! (01)
May 17 19:08:10 secant kernel: i2c i2c-0: Failed! (01)
May 17 19:08:10 secant kernel: i2c i2c-0: Failed! (01)
...
May 17 19:08:11 secant kernel: i2c i2c-0: Failed! (01)
May 17 19:08:11 secant kernel: i2c i2c-0: Failed! (01)
May 17 19:08:11 secant kernel: i2c i2c-0: Failed! (01)
May 17 19:08:11 secant kernel: i2c i2c-0: Failed! (01)

 

The closest relevant thing I could find with a quick search was this : https://ubuntu-mate.community/t/i2c-i2c-2-smbus-timeout-at-boot-upgraded-to-new-kernel-5-0-0-21/19947/4

 

Maybe something in the kernel is checking SMBus and constantly spamming the logs when failing ? I am using the modules "k10temp nct6775 jc42" in the Dynamix System Temperature, should I uninstall that plugin?

 

Hoping someone has seen something similar or has suggestions on how to mitigate this.

 

Thanks.

Edited May 18, 2021 by h1d3m3

[h1d3m3]

Ok. Tried a few things.

 

First, I unloaded all of the drivers that were detected in system temp plugin. That seems to have stemmed the tide of syslog failure messages.

 

Second, I think I have isolated the problem to the jc42 kernel module that is detected and loaded with the sensor plugin. When that is removed (now I only have "k10temp nct6775" listed), the error messages seems to have gone away. This is kind of a bummer because I no longer have my CPU (die) sensors available to select.

 

I'm not 100% sure the problem is actually jc42 related (it could have been just unloading the modules or maybe it will show up again), but at least it has stopped for now.

Edited May 18, 2021 by h1d3m3

[John_M]

There's a lot of information about the jc42 and other hwmon modules here: https://www.kernel.org/doc/html/latest/hwmon/jc42.html