RE: k10temp show over 100 degrees temperature on EPYC Milan servers from DELL and SMC

[Limonciello, Mario]

[Public]

Hi,

> Dear experts on the list,
> 
> We've noticed many of our EPYC Milan servers from different vendors
> (DELL  and SMC) show 100 degrees, eg
> 
> sudo sensors
> k10temp-pci-00c3
> Adapter: PCI adapter
> Tctl:        +117.5°C
> Tdie:        +117.5°C
> Tccd1:        +67.0°C
> Tccd2:        +65.2°C
> Tccd3:        +63.2°C
> Tccd4:        +63.8°C
> Tccd5:        +67.2°C
> Tccd6:        +63.5°C
> Tccd7:        +64.2°C
> Tccd8:        +64.8°C
> 
>  sudo lscpu
> Architecture:                    x86_64
> CPU op-mode(s):                  32-bit, 64-bit
> Byte Order:                      Little Endian
> Address sizes:                   48 bits physical, 48 bits virtual
> CPU(s):                          128
> On-line CPU(s) list:             0-127
> Thread(s) per core:              2
> Core(s) per socket:              64
> Socket(s):                       1
> NUMA node(s):                    1
> Vendor ID:                       AuthenticAMD
> CPU family:                      25
> Model:                           1
> Model name:                      AMD EPYC 7713P 64-Core Processor
> Stepping:                        1
> Frequency boost:                 enabled
> CPU MHz:                         2479.705
> CPU max MHz:                     3720,7029
> CPU min MHz:                     1500,0000
> BogoMIPS:                        3992.43
> Virtualization:                  AMD-V
> L1d cache:                       2 MiB
> L1i cache:                       2 MiB
> L2 cache:                        32 MiB
> L3 cache:                        256 MiB
> NUMA node0 CPU(s):               0-127
> 
> We've seen such high temperatures even on  idle servers.
> 
> We are running LTS kernel 5.10.136, but checking the git history for
> k10temp driver, I don't find any missing fix.
> My questions are:
> 1. Is it normal to have such high temperatures for tctl?  can we trust
> the value?
> 2  Do we need to worry about such high temperatures?
> 
> Thx!
> Jinpu Wang @ IONOS Cloud.

It's fixed by this patch that will be going into 6.4.
https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git/commit/?h=hwmon-next&id=1dc8e097967b69a56531c9ccb70b854771310e85

Guenter,

If you didn't already send your 6.4 PR, can you please add
Cc: stable@xxxxxxxxxxxxxxx to the patch in your tree?

Thanks,