[i915] Screen "disconnects" when updating screen buffer

[Johannes Konow]

I have a problem in which the screen will behave as if I pulled the HDMI or turned the computer off (no source) for a few seconds until the screen comes back on again. This happens a lot when I open a new window, moves the mouse after it has been still for a while or I open a new window or move the current window.

I can watch a whole movie without this problem but as soon as I pause or touch the controls of VLC or move the mouse the problem reocurr. It seems to be after a certain idle period most of the time, but not always. Sometimes it happens many times in a row.

The setup is my home built media PC with intel integrated graphics (i5-9400) connected to a philips 55" TV (55POS901F) through a Pioneer AV receiver.

I have tried probably every possible resolution and screen update frequency and the problem is still there.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: xorg 1:7.7+19ubuntu14
ProcVersionSignature: Ubuntu 5.4.0-66.74-generic 5.4.86
Uname: Linux 5.4.0-66-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.16
Architecture: amd64
BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
CasperMD5CheckResult: skip
CompositorRunning: None
CurrentDesktop: ubuntu:GNOME
Date: Sat Apr 24 21:57:54 2021
DistUpgraded: 2020-12-01 07:11:08,428 DEBUG Running PostInstallScript: './xorg_fix_proprietary.py'
DistroCodename: focal
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes
GraphicsCard:
 Intel Corporation UHD Graphics 630 (Desktop 9 Series) [8086:3e98] (rev 02) (prog-if 00 [VGA controller])
   Subsystem: ASRock Incorporation UHD Graphics 630 (Desktop 9 Series) [1849:3e98]
InstallationDate: Installed on 2020-12-01 (144 days ago)
InstallationMedia: Ubuntu 18.04.2 LTS "Bionic Beaver" - Release amd64 (20190210)
Lsusb:
 Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
 Bus 001 Device 003: ID 8087:0aa7 Intel Corp.
 Bus 001 Device 002: ID 046d:c52b Logitech, Inc. Unifying Receiver
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: To Be Filled By O.E.M. To Be Filled By O.E.M.
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-5.4.0-66-generic root=/dev/mapper/ubuntu--vg-root ro quiet splash vt.handoff=7
SourcePackage: xorg
Symptom: display
UpgradeStatus: Upgraded to focal on 2020-12-01 (144 days ago)
dmi.bios.date: 05/14/2019
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: P4.10
dmi.board.name: H310CM-ITX/ac
dmi.board.vendor: ASRock
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: To Be Filled By O.E.M.
dmi.chassis.version: To Be Filled By O.E.M.
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrP4.10:bd05/14/2019:svnToBeFilledByO.E.M.:pnToBeFilledByO.E.M.:pvrToBeFilledByO.E.M.:rvnASRock:rnH310CM-ITX/ac:rvr:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.:
dmi.product.family: To Be Filled By O.E.M.
dmi.product.name: To Be Filled By O.E.M.
dmi.product.sku: To Be Filled By O.E.M.
dmi.product.version: To Be Filled By O.E.M.
dmi.sys.vendor: To Be Filled By O.E.M.
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.102-1ubuntu1~20.04.1
version.libgl1-mesa-dri: libgl1-mesa-dri 20.2.6-0ubuntu0.20.04.1
version.libgl1-mesa-glx: libgl1-mesa-glx 20.2.6-0ubuntu0.20.04.1
version.xserver-xorg-core: xserver-xorg-core 2:1.20.9-2ubuntu1.2~20.04.2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:19.1.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20200226-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.16-1

[Daniel van Vugt (vanvugt)]

This sounds like an HDMI connection/signalling problem. Please check to see if a direct connection (no receiver), and even a new cable, exhibits the same problem.

[Johannes Konow (itix)]

Most certainly not a problem with hdmi connection. I have had windows installed on the same machine without issues. The behavior is such that it is very clear that as soon as you move the mouse after a period of idle, the problem occurs. Also if the computer receives a notification after a period of idle it occurs.

There is a definite link to activity which renders new information on the screen buffer. It can play a movie without a problem on vlc but when I pause, it disconnects the screen (presumably because the "pause" bars appear on the screen). If I right click to add subtitles or change something else in the video it also appears at the exact same time I click. This problem is very repeatable. I can do a phone quality video if that would be of interest.

If it was a problem with hdmi it would be more random in behavior and it would be a problem on windows as well.

[Daniel van Vugt (vanvugt)]

There certainly are invisible differences between Linux and Windows kernels internally how they implement HDMI signalling. So it is possible Linux is more fragile than Windows in this respect. As such, avoiding the receiver or changing cables might be a workaround.

A proper fix in that case would go in the kernel so reassigning there...

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]

[Johannes Konow (itix)]

This problem is persisting and today I noticed something I think might help pinpoint the problem.

I was playing a slide show in shotwell when the screen went black again and when it came back on after a few seconds, the last picture displayed was stuck and the new pictures were displaying in a corner in a much smaller frame as if the system just tried to reset the resolution to something much smaller and then changed its mind and reverted (but shotwell didn't get the message and kept rendering to the small resolution rather than the wide one).

Hope this helps to pinpoint the issue.

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

This change was made by a bot.

[Daniel van Vugt (vanvugt)]

Johannes,

The problem in comment #6 sounds like a hotplug event, like the whole HDMI connection was lost and then reconnected.

Next time the problem happens please immediately run:

  journalctl -b0 > journal.txt

and attach the resulting text file here.

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]