kworker constantly burns CPU in intel HPD detection code

[Richard]

In recent kernels (since the ~18th of January as far as I can tell based on my load average graphs), kworker has been burning a CPU core polling for HDMI HDP events on one of my machines, this is obviously bad :)

I've attached a perf trace (running on 5.3.0-40-generic) and also here's a screenshot showing the offending trace:

https://imgur.com/a/4WO2pn6

Let me know if I can provide any extra information.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: linux-image-5.3.0-40-generic 5.3.0-40.32~18.04.1
ProcVersionSignature: Ubuntu 5.3.0-40.32~18.04.1-generic 5.3.18
Uname: Linux 5.3.0-40-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.11
Architecture: amd64
Date: Thu Feb 20 18:01:05 2020
InstallationDate: Installed on 2018-01-02 (778 days ago)
InstallationMedia: Ubuntu-Server 16.04.3 LTS "Xenial Xerus" - Release amd64 (20170801)
SourcePackage: linux-signed-hwe
UpgradeStatus: Upgraded to bionic on 2018-09-03 (534 days ago)