[Bug 1813663] Re: External monitors does not work anymore 4.15.0-44

I can confirm I'm having the same problem with a Dell Precision 5510
laptop. I have traced the problem to the startup item "/usr/lib/x86_64
-linux-gnu/cinnamon-settings-daemon/csd-xrandr" it seems xrandr is
freezing the system when it boots up connected to a Thunderbolt 3 Dock.

If I disable that startup item, I can boot up while docked just fine, I
just can't change my monitoring configuration around. If I boot up using
the 4.15.0-43-generic kernel, that startup option works just fine and
everything works.

Somehow linux-image-4.15.0-44-generic has changed how the video card
works with Dell laptops and Thunderbolt 3 docks; as soon as xrandr tries
to fully initialize the graphics cards everything freezes up.

--
You received this bug notification because you are subscribed to linux
in Ubuntu.
Matching subscriptions: Bgg, Bmail, Nb
https://bugs.launchpad.net/bugs/1813663

Title:
External monitors does not work anymore 4.15.0-44

Status in linux package in Ubuntu:
Confirmed
Status in linux source package in Bionic:
Fix Committed

Bug description:
I am using a docking station for my laptop. After install the
4.15.0-44 update my external monitors goes undetected after logging in
or having the laptop closed.

I am on 18.04.1 LTS with Intel® HD Graphics 620 (Kaby Lake GT2)
Graphics.

Going back to the 4.15.0-43 version makes it all work fine again.
---
ProblemType: Bug
ApportVersion: 2.20.9-0ubuntu7.5
Architecture: amd64
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/controlC0: jonas 2407 F.... pulseaudio
CurrentDesktop: ubuntu:GNOME
DistroRelease: Ubuntu 18.04
HibernationDevice: RESUME=UUID=80397b76-2ded-4f7d-adbf-dfdface8e2d4
InstallationDate: Installed on 2018-10-17 (103 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
MachineType: LENOVO 20HF004MMX
Package: linux (not installed)
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-44-generic root=UUID=64cf1582-d574-4e2f-a40a-7942c40caf5d ro quiet splash vt.handoff=1
ProcVersionSignature: Ubuntu 4.15.0-44.47-generic 4.15.18
RelatedPackageVersions:
linux-restricted-modules-4.15.0-44-generic N/A
linux-backports-modules-4.15.0-44-generic N/A
linux-firmware 1.173.3
Tags: bionic
Uname: Linux 4.15.0-44-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip docker kvm lpadmin plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 09/14/2018
dmi.bios.vendor: LENOVO
dmi.bios.version: N1WET51W (1.30 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20HF004MMX
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40697 WIN
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrN1WET51W(1.30):bd09/14/2018:svnLENOVO:pn20HF004MMX:pvrThinkPadT470s:rvnLENOVO:rn20HF004MMX:rvrSDK0J40697WIN:cvnLENOVO:ct10:cvrNone:
dmi.product.family: ThinkPad T470s
dmi.product.name: 20HF004MMX
dmi.product.version: ThinkPad T470s
dmi.sys.vendor: LENOVO

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1813663/+subscriptions