Public bug reported:

LSB Release: Ubuntu 19.10
Package: linux-image-5.3.0-23-generic
Hardware:  System76 Galago Pro v4 (i7-8750H), Clevo-960rd (i7-9750H)

Expected results:
CPU should be governed by Intel P-State and should normally idle between 400 
and 800 MHz when not loaded.

Actual results:
After update, CPU frequency remains pegged at maximum at all times.  This sucks 
battery life and overheats the laptop.

Steps to reproduce:
1. Install Ubuntu 19.10 from official media. Kernel installed will be 
5.3.0-18-generic
2. Check CPU frequencies. They will typically idle around 800MHz.  Loading the 
system will spike to max frequencies (4.5 for 9750H, 4.2 for 8750H).
3. Upgrade system. Kernel will update to 5.3.0-23-generic
4. Reboot.
5. Monitor CPU frequencies again. This time, all core will remain at max 
frequencies.

Additional information:

1. Geekbench v4 multi-core scores are cut in half (26K vs 13K) after update. 
Single-core scores drop around 20%.  This does not occur in 19.04 or 18.04. 
Confirmed on multiple 960rd systems.
2. linux-image-5.3.0-19-generic is also confirmed
3. We suspect that all kernels images after 5.3.0-18 have this bug
4. We are not sure how much hardware is affected. At present, only the 
8750/9750H CPUs are confirmed.

** Affects: powertop (Ubuntu)
     Importance: Undecided
         Status: New

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https://bugs.launchpad.net/bugs/1855178

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