[Bug 1970495] Re: Window manager freezes when plugging in USB-C dock with external monitor ([drm] *ERROR* mstb 00000000f21f0a30 port 1: DPCD read on addr 0x4b0 for 1 bytes NAKed)

I can reproduce this issue, too.
When plug in the dock(with HDMI 4k monitor), the screen freeze and keyboard/touchpad won't work, but I still can ssh into the machine.
Un-plug the dock, everything works again.

BTW, I found gnome-shell runs in 100% while the issue happened, and un-
plug the dock the CPU usage of gnome-shell comes back to normal.

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Title:
Window manager freezes when plugging in USB-C dock with external
monitor ([drm] *ERROR* mstb 00000000f21f0a30 port 1: DPCD read on addr
0x4b0 for 1 bytes NAKed)

Status in linux package in Ubuntu:
Confirmed
Status in mutter package in Ubuntu:
Confirmed

Bug description:
1. Problem DOES appear on Lenovo T470s (Intel).
2. Problem DOES appear on Lenovo T14 Gen2 (AMD).
3. Problem does NOT appear on either of the above *when in the Live Installer*.

I specifically checked that my dock behaved well under the Live
Installer before deciding to move my workstations to Jammy. Upon
logging into a fresh Jammy install, I found the following problem
behavior: When the dock is plugged in, the built-in display freezes
and the dock-attached displays power up but never render anything (ie,
they stay black). Unplugging the USB-C cable gets mouse/keyboard
response back on the built-in display.

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: gnome-shell 42.0-2ubuntu1
ProcVersionSignature: Ubuntu 5.15.0-27.28-generic 5.15.30
Uname: Linux 5.15.0-27-generic x86_64
ApportVersion: 2.20.11-0ubuntu82
Architecture: amd64
CasperMD5CheckResult: pass
CurrentDesktop: ubuntu:GNOME
Date: Tue Apr 26 18:32:35 2022
DisplayManager: gdm3
InstallationDate: Installed on 2022-04-26 (0 days ago)
InstallationMedia: Ubuntu 22.04 LTS "Jammy Jellyfish" - Release amd64 (20220419)
ProcEnviron:
TERM=xterm-256color
PATH=(custom, no user)
XDG_RUNTIME_DIR=<set>
LANG=en_US.UTF-8
SHELL=/bin/bash
RelatedPackageVersions: mutter-common 42.0-3ubuntu2
SourcePackage: gnome-shell
UpgradeStatus: No upgrade log present (probably fresh install)

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