Thinkpad x220 - Unable to use 2560x1440 external display connected via DisplayPort due flashing black screen

[Adam Kessel]

I have a fresh install of 18.10 on an old Thinkpad x220. Everything works fine with the internal display or an external Dell G2410 (1920x1080) connected via VGA. But when I try to switch to an external BenQ PD2710QC (2560x1440) I only see the screen for a few seconds at a time and then it flashes to black. This happens consistently for minutes--it never "settles down".

I've tried the default configuration as well as copying xorg.conf from /usr/share/doc/xserver-xorg-video-intel into /etc/x11. I've tried both xorg configurations with nomodeset in the bootloader and without. I have not been able to find any configuration that allows this external DisplayPort display to work.

The same hardware combination works fine in Windows 10.

ProblemType: Bug
DistroRelease: Ubuntu 18.10
Package: xorg 1:7.7+19ubuntu8
ProcVersionSignature: Ubuntu 4.18.0-10.11-generic 4.18.12
Uname: Linux 4.18.0-10-generic x86_64
ApportVersion: 2.20.10-0ubuntu13
Architecture: amd64
Date: Fri Nov 9 13:10:59 2018
DistUpgraded: Fresh install
DistroCodename: cosmic
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes
GraphicsCard:
 Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0126] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: Lenovo 2nd Generation Core Processor Family Integrated Graphics Controller [17aa:21da]
InstallationDate: Installed on 2018-11-09 (0 days ago)
InstallationMedia: Ubuntu 18.10 "Cosmic Cuttlefish" - Release amd64 (20181017.3)
MachineType: LENOVO 42872WU
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.18.0-10-generic root=UUID=cd4f21be-48dd-48e7-b289-a59a32bd0be3 ro quiet splash nomodeset vt.handoff=1
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)
XorgConf:
 Section "Device"
  Identifier "Intel"
  Driver "intel"
 # Option "AccelMethod" "uxa"
 EndSection
dmi.bios.date: 06/21/2018
dmi.bios.vendor: LENOVO
dmi.bios.version: 8DET76WW (1.46 )
dmi.board.asset.tag: Not Available
dmi.board.name: 42872WU
dmi.board.vendor: LENOVO
dmi.board.version: Not Available
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvr8DET76WW(1.46):bd06/21/2018:svnLENOVO:pn42872WU:pvrThinkPadX220:rvnLENOVO:rn42872WU:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.family: ThinkPad X220
dmi.product.name: 42872WU
dmi.product.version: ThinkPad X220
dmi.sys.vendor: LENOVO
version.compiz: compiz 1:0.9.13.1+18.10.20180930-0ubuntu1
version.libdrm2: libdrm2 2.4.95-1
version.libgl1-mesa-dri: libgl1-mesa-dri 18.2.2-0ubuntu1
version.libgl1-mesa-glx: libgl1-mesa-glx N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.20.1-3ubuntu2.1
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.1.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20171229-1ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-3

[Daniel van Vugt (vanvugt)]

Can you please try logging into "Ubuntu on Wayland" and tell us if that has the same problem?

[Adam Kessel (adam-rosi-kessel)]

I'm having trouble finding a way to switch Ubuntu 18.10 to Wayland. I have Xwayland installed but don't see a way to switch the session. I did enable it in gdm3 custom.conf but it doesn't seem to be running. Can you point me to some directions?

[Daniel van Vugt (vanvugt)]

On the login screen, click on the gear (cog) icon :)

[Adam Kessel (adam-rosi-kessel)]

I can't even get into the login screen when the DisplayPort device is attached. But I disconnected that, got to gdm login via the VGA device, then switched to Ubuntu on Wayland. Ubuntu on Wayland works fine for me generally, but I get the same behavior when connecting the DisplayPort device after logging in. I've included a video of the behavior here: https://photos.app.goo.gl/aJSx5stMMg7QZULH6

[Daniel van Vugt (vanvugt)]

If you get the same behaviour in Wayland sessions then it's probably not a Xorg bug. Maybe mutter or maybe the kernel.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This change was made by a bot.

[Joseph Salisbury (jsalisbury)]

Did this issue start happening after an update/upgrade? Was there a prior kernel version where you were not having this particular problem?

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.20 kernel[0].

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.20-rc3

[Adam Kessel (adam-rosi-kessel)]

This machine is a fresh install so there have been no updates/upgrades. The initial install was 18.10 and whatever kernel came by default with that. I will test with the latest upstream kernel and report back.

[Adam Kessel (adam-rosi-kessel)]

I installed vmlinuz-4.20.0-042000rc3-generic per your request. The machine won't boot, and just loops infinitely with the error message:

request_module: kmod_concurrent_max (0) close to 0 (max_modprobes: 50), for module binfmt-646c, throttling...
request_module: modprobe binfmt-646c cannot be processed, kmod busy with 50 threads for more than 5 seconds now

I've done some googling and don't see an obvious fix. Any suggestions?

[Daniel van Vugt (vanvugt)]

I suggest trying a more stable newer version in that case, like:
  http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.19.2/

[Adam Kessel (adam-rosi-kessel)]

No luck with 4.19.2 either -- kernel panic (recovery mode or normal boot).

[Daniel van Vugt (vanvugt)]

Thank you for reporting this bug to Ubuntu.
Ubuntu 18.10 (cosmic) reached end-of-life on July 18, 2019.

See this document for currently supported Ubuntu releases:
https://wiki.ubuntu.com/Releases

We appreciate that this bug may be old and you might not be interested in discussing it any more. But if you are then please upgrade to the latest Ubuntu version and re-test. If you then find the bug is still present in the newer Ubuntu version, please add a comment here telling us which new version it is in and change the bug status to Confirmed.