[FSL P50x0] lscpu reports wrong values since the RC1 of kernel 5.13

Srikar Dronamraju srikar at linux.vnet.ibm.com
Thu Aug 26 13:43:10 AEST 2021


* Christian Zigotzky <chzigotzky at xenosoft.de> [2021-08-16 14:29:21]:


Hi Christian,

> I tested the RC6 of kernel 5.14 today and unfortunately the issue still
> exists. We have figured out that only P5040 SoCs are affected. [1]
> P5020 SoCs display the correct values.
> Please check the CPU changes in the PowerPC updates 5.13-1 and 5.13-2.
>

Thanks for reporting the issue.
Would it be possible to try
https://lore.kernel.org/linuxppc-dev/20210821092419.167454-3-srikar@linux.vnet.ibm.com/t/#u

If the above patch is not helping, then can you please collect the output of

cat /sys/devices/system/cpu/cpu*/topology/core_siblings

Were all the CPUs online at the time of boot?
Did we do any CPU online/offline operations post boot?

If we did CPU online/offline, can you capture the output just after the
boot along with lscpu output..

Since this is being seen on few SOCs, can you summarize the difference
between P5040 and P5020.
> 
> [1] https://forum.hyperion-entertainment.com/viewtopic.php?p=53775#p53775
> 
> 
> On 09 August 2021 um 02:37 pm, Christian Zigotzky wrote:
> > Hi All,
> > 
> > Lscpu reports wrong values [1] since the RC1 of kernel 5.13 on my FSL
> > P5040 Cyrus+ board (A-EON AmigaOne X5000). [2]
> > The differences are:
> > 
> > Since the RC1 of kernel 5.13 (wrong values):
> > 
> > Core(s) per socket: 1
> > Socket(s): 3
> > 

I know that the socket count was off by 1, but I cant explain how its off by
2 here.

> > Before (correct values):
> > 
> > Core(s) per socket: 4
> > Socket(s): 1
> > 

-- 
Thanks and Regards
Srikar Dronamraju


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