Error in CPU frequency reporting when nominal and min pstates are same (cpufreq)

I built a test kernel with commit 3fa4680b860bf48b437d6a2c039789c4abe202ae. The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1746174

Can you test this kernel and see if it resolves this bug?

Note, to test this kernel, you need to install both the linux-image and linux-image-extra .deb packages.

Thanks in advance!

------- Comment From <email address hidden> 2018-02-15 05:03 EDT-------
Hi,

I have tested the kernel and is working as expected.

root@bostonp9:~# uname -a
Linux bostonp9 4.13.0-17-generic #20~lp1746174 SMP Tue Jan 30 20:48:25 UTC 2018 ppc64le ppc64le ppc64le GNU/Linux

[ 4.443270] powernv-cpufreq: cpufreq pstate min 81 nominal 81 max 0
[ 4.443318] powernv-cpufreq: Workload Optimized Frequency is enabled in the platform

Thanks and Regards,
Shilpa

SRU request submitted:
https://lists.ubuntu.com/archives/kernel-team/2018-February/090263.html

------- Comment From <email address hidden> 2018-02-26 06:09 EDT-------
Hi ,
Can you please let us know in which build the fix is available ?

I am able to see issue on :

root@ltc-boston27:~# dmesg | grep freq
[ 0.000000] time_init: decrementer frequency = 512.000000 MHz
[ 0.000000] time_init: processor frequency = 2134.000000 MHz
[ 2.159457] powernv-cpufreq: cpufreq pstate min 98 nominal 98 max 0
[ 2.159459] powernv-cpufreq: Workload Optimized Frequency is enabled in the platform
[ 2.164178] powernv-cpufreq: pstate 97 is out of bound

ubuntu@ltc-boston27:~$ uname -a
Linux ltc-boston27 4.15.0-10-generic #11-Ubuntu SMP Tue Feb 13 18:21:52 UTC 2018 ppc64le ppc64le ppc64le GNU/Linux

The bug is in progress, thus the fix for this issues is not yet available for testing.
When it is available, there will be a comment on this bug report, calling for testing and listing exact version number of the kernel which includes the fix.

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-artful' to 'verification-done-artful'. If the problem still exists, change the tag 'verification-needed-artful' to 'verification-failed-artful'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

This bug was fixed in the package linux - 4.13.0-38.43

---------------
linux (4.13.0-38.43) artful; urgency=medium

  * linux: 4.13.0-38.43 -proposed tracker (LP: #1755762)

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    - i40e: Add programming descriptors to cleaned_count

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  * fails to dump with latest kpti fixes (LP: #1750021)
    - kdump: write correct address of mem_section into vmcoreinfo

  * headset mic can't be detected on two Dell machines (LP: #1748807)
    - ALSA: hda/realtek - Support headset mode for ALC215/ALC285/ALC289
    - ALSA: hda - Fix headset mic detection problem for two Dell machines
    - ALSA: hda - Fix a wrong FIXUP for alc289 on Dell machines

  * CIFS SMB2/SMB3 does not work for domain based DFS (LP: #1747572)
    - CIFS: make IPC a regular tcon
    - CIFS: use tcon_ipc instead of use_ipc parameter of SMB2_ioctl
    - CIFS: dump IPC tcon in debug proc file

  * i2c-thunderx: erroneous error message "unhandled state: 0" (LP: #1754076)
    - i2c: octeon: Prevent error message on bus error

  * hisi_sas: Add disk LED support (LP: #1752695)
    - scsi: hisi_sas: directly attached disk LED feature for v2 hw

  * EDAC, sb_edac: Backport 1 patch to Ubuntu 17.10 (Fix missing DIMM sysfs
    entries with KNL SNC2/SNC4 mode) (LP: #1743856)
    - EDAC, sb_edac: Fix missing DIMM sysfs entries with KNL SNC2/SNC4 mode

  * [regression] Colour banding and artefacts appear system-wide on an Asus
    Zenbook UX303LA with Intel HD 4400 graphics (LP: #1749420)
    - drm/edid: Add 6 bpc quirk for CPT panel in Asus UX303LA

  * DVB Card with SAA7146 chipset not working (LP: #1742316)
    - vmalloc: fix __GFP_HIGHMEM usage for vmalloc_32 on 32b systems

  * [Asus UX360UA] battery status in unity-panel is not changing when battery is
    being charged (LP: #1661876) // AC adapter status not detected on Asus
    ZenBook UX410UAK (LP: #1745032)
    - ACPI / battery: Add quirk for Asus UX360UA and UX410UAK

  * ASUS UX305LA - Battery state not detected correctly (LP: #1482390)
    - ACPI / battery: Add quirk for Asus GL502VSK and UX305LA

  * support thunderx2 vendor pmu events (LP: #1747523)
    - perf pmu: Extract function to get JSON alias map
    - perf pmu: Pass pmu as a parameter to get_cpuid_str()
    - perf tools arm64: Add support for get_cpuid_str function.
    - perf pmu: Add helper function is_pmu_core to detect PMU CORE devices
    - perf vendor events arm64: Add ThunderX2 implementation defined pmu core
      events
    - perf pmu: Add check for valid cpuid in perf_pmu__find_map()

  * lpfc.ko module doesn't work (LP: #1746970)
    - scsi: lpfc: Fix loop mode target discovery

  * Ubuntu 17.10 crashes on vmalloc.c (LP: #1739498)
    - powerpc/mm/book3s64: Make KERN_IO_START a variable
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    - powerpc/mm/hash64: Make vmalloc 56T on hash

  * ethtool -p fails to light NIC LED on HiSilicon D05 systems (LP: #1748567)
    - net...

Marking bionic as fix-released, since the patch identified here is in bionic-master
cf0de9a0d52f cpufreq: powernv: Dont assume distinct pstate values for nominal and pmin