Screen and keyboard frozen on login on Lenovo Thinkpad X220

[Andre]

Until Kernel 4.4.0-166-generic everything was working fine, but since then an update (maybe CVE-2019-14615 ?) made it impossible to log into my laptop.

Symptom: after an unusual long boot time, the login screen appears. It is not possible to type my password. It is not possible to move the mouse. After screen timeout the screen goes into powersave. Hitting any key or moving the mouse doesn't wake it up.

Observed on Kernels:
* 4.4.0-173-generic
* 4.15.0-74-generic
* 4.15.0-76-generic

To be able to file this bug, I have SSHed into my laptop.

To be able to use my laptop, I need to boot into the older Kernel 4.4.0-166

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: linux-image-4.15.0-76-generic 4.15.0-76.86~16.04.1
ProcVersionSignature: Ubuntu 4.15.0-76.86~16.04.1-generic 4.15.18
Uname: Linux 4.15.0-76-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.21
Architecture: amd64
Date: Sun Feb 9 16:54:28 2020
EcryptfsInUse: Yes
InstallationDate: Installed on 2012-03-24 (2877 days ago)
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
SourcePackage: linux-signed-hwe
UpgradeStatus: Upgraded to xenial on 2019-04-14 (300 days ago)