[nvidia] multimonitor ghostly flickering display artifacts

[nixderek]

https://gitlab.gnome.org/GNOME/mutter/issues/175

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On Ubuntu 18.04, running nvidia-390 driver (on a GTX 1080), and gnome shell 3.28.1.

I have a 3 monitor setup. When I open a terminal in the middle window and some other window, like nautilus on the left, and quickly drag the nautilus window to the right, covering the terminal, and back without releasing the mouse, a flickering ghost of the window remains on the terminal for about a minute or so.
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ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
DisplayManager: gdm3
DistroRelease: Ubuntu 18.04
GsettingsChanges:
 b'org.gnome.shell' b'favorite-apps' redacted by apport
 b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'"
 b'org.gnome.desktop.interface' b'clock-format' b"'12h'"
InstallationDate: Installed on 2018-05-10 (15 days ago)
InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426)
NonfreeKernelModules: nvidia_modeset nvidia
Package: mutter
PackageArchitecture: amd64
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 4.15.0-22.24-generic 4.15.17
Tags: bionic
Uname: Linux 4.15.0-22-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True

[Daniel van Vugt (vanvugt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. Please execute the following command only once, as it will automatically gather debugging information, in a terminal:

apport-collect 1770731

When reporting bugs in the future please use apport by using 'ubuntu-bug' and the name of the package affected. You can learn more about this functionality at https://wiki.ubuntu.com/ReportingBugs.

[Daniel van Vugt (vanvugt)]

Please also run this command and send us the output:

  lspci -k

[nixderek (nixderek)]

apport information

[nixderek (nixderek)]

apport information

[nixderek (nixderek)]

$ lspci -k
00:00.0 Host bridge: Intel Corporation Intel Kaby Lake Host Bridge (rev 05)
 Subsystem: ASRock Incorporation Intel Kaby Lake Host Bridge
00:01.0 PCI bridge: Intel Corporation Skylake PCIe Controller (x16) (rev 05)
 Kernel driver in use: pcieport
 Kernel modules: shpchp
00:14.0 USB controller: Intel Corporation 200 Series PCH USB 3.0 xHCI Controller
 Subsystem: ASRock Incorporation 200 Series PCH USB 3.0 xHCI Controller
 Kernel driver in use: xhci_hcd
00:14.2 Signal processing controller: Intel Corporation 200 Series PCH Thermal Subsystem
 Subsystem: ASRock Incorporation 200 Series PCH Thermal Subsystem
00:16.0 Communication controller: Intel Corporation 200 Series PCH CSME HECI #1
 Subsystem: ASRock Incorporation 200 Series PCH CSME HECI
 Kernel driver in use: mei_me
 Kernel modules: mei_me
00:17.0 SATA controller: Intel Corporation 200 Series PCH SATA controller [AHCI mode]
 Subsystem: ASRock Incorporation 200 Series PCH SATA controller [AHCI mode]
 Kernel driver in use: ahci
 Kernel modules: ahci
00:1b.0 PCI bridge: Intel Corporation 200 Series PCH PCI Express Root Port #17 (rev f0)
 Kernel driver in use: pcieport
 Kernel modules: shpchp
00:1c.0 PCI bridge: Intel Corporation 200 Series PCH PCI Express Root Port #1 (rev f0)
 Kernel driver in use: pcieport
 Kernel modules: shpchp
00:1c.1 PCI bridge: Intel Corporation 200 Series PCH PCI Express Root Port #2 (rev f0)
 Kernel driver in use: pcieport
 Kernel modules: shpchp
00:1c.2 PCI bridge: Intel Corporation 200 Series PCH PCI Express Root Port #3 (rev f0)
 Kernel driver in use: pcieport
 Kernel modules: shpchp
00:1c.4 PCI bridge: Intel Corporation 200 Series PCH PCI Express Root Port #5 (rev f0)
 Kernel driver in use: pcieport
 Kernel modules: shpchp
00:1c.7 PCI bridge: Intel Corporation 200 Series PCH PCI Express Root Port #8 (rev f0)
 Kernel driver in use: pcieport
 Kernel modules: shpchp
00:1d.0 PCI bridge: Intel Corporation 200 Series PCH PCI Express Root Port #9 (rev f0)
 Kernel driver in use: pcieport
 Kernel modules: shpchp
00:1f.0 ISA bridge: Intel Corporation 200 Series PCH LPC Controller (Z270)
 Subsystem: ASRock Incorporation 200 Series PCH LPC Controller (Z270)
00:1f.2 Memory controller: Intel Corporation 200 Series PCH PMC
 Subsystem: ASRock Incorporation 200 Series PCH PMC
00:1f.3 Audio device: Intel Corporation 200 Series PCH HD Audio
 Subsystem: ASRock Incorporation 200 Series PCH HD Audio
 Kernel driver in use: snd_hda_intel
 Kernel modules: snd_hda_intel
00:1f.4 SMBus: Intel Corporation 200 Series PCH SMBus Controller
 Subsystem: ASRock Incorporation 200 Series PCH SMBus Controller
 Kernel modules: i2c_i801
00:1f.6 Ethernet controller: Intel Corporation Ethernet Connection (2) I219-V
 Subsystem: ASRock Incorporation Ethernet Connection (2) I219-V
 Kernel driver in use: e1000e
 Kernel modules: e1000e
01:00.0 VGA compatible controller: NVIDIA Corporation GP104 [GeForce GTX 1080] (rev a1)
 Subsystem: eVga.com. Corp. GP104 [GeForce GTX 1080]
 Kernel driver in use: nvidia
 Kernel modules: nvidiafb, nouveau, nvidia_drm, nvidia
01:00.1 Audio device: NVIDIA Corporation GP104 High Definition Audio Controller (rev a1)
 Subsystem: eVga.com. Corp. GP104 High Definition Audio ...

[Daniel van Vugt (vanvugt)]

Flickering ghost images may be caused by gnome-shell's damage tracking losing track of where things have been drawn, and it then uses buffer age information incorrectly, leaving junk in only one of the buffers (out of 2 or 3). So every second or third frame contains pixels that shouldn't be there, 20 or 30 times per second. I think the best way to work around it is to drag a window over the flickering area.

Also, please report this bug to the Gnome developers here:
https://gitlab.gnome.org/GNOME/mutter/issues

[Daniel van Vugt (vanvugt)]

... and then let us know the URL of the new bug.

[nixderek (nixderek)]

Gnome bug link: https://gitlab.gnome.org/GNOME/mutter/issues/175