Public bug reported: The following Xorg configuration triggers faulty behaviour, like blinking cursor, corrupt graphics around it etc.:
1 Section "Device" 2 Identifier "graphicsdriver" 3 Driver "modesetting" 4 Option "SWCursor" "true" 5 #Option "PageFlip" "off" 6 #Option "AccelMethod" "none" 7 EndSection Either switching SWCursor to false or uncommenting line 5 or 6 makes the issue disappear. Disabling accelleration is naturally the least recommended way of resolving the issue. As far as I've analyzed Xorg's source code shipped with 20.04, I can see that https://gitlab.freedesktop.org/xorg/xserver/commit/0aaac8d783e78c040a70a55ba8d67809abd7e625 which should probably automatically handle the issue (haven't tried to build with those changes yet) is not included. If it ever should be in (as it looks like a workaround only), reamains an open question. I am not entirely sure which package to attach this bug to, Xorg seems the most viable at the moment. My reason for the uncertainty originates from the fact, that I have also tested other distros, e.g. SuSE tumbleweed (build from this week, exact versions to be added if needed) with KDE plasma, which happens to reproduce the bug only with OpenGL set as compositor's backend; XRender operates perfectly fine there; hence it is a bit unclear to me which compoment is the "owning interface" and which one is actually buggy, be it Xorg, mesa or compositor; please reassign the bug accordingly if needed. My plan for the nearest future is to verify whether the aforementioned change actually circumvents the issue. If anything else should be looked at to fix the problem, I am open for suggestions. ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: xserver-xorg-core 2:1.20.7-2ubuntu2 ProcVersionSignature: Ubuntu 5.4.0-21.25-generic 5.4.27 Uname: Linux 5.4.0-21-generic x86_64 ApportVersion: 2.20.11-0ubuntu21 Architecture: amd64 BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log' CompositorRunning: None CurrentDesktop: ubuntu:GNOME Date: Fri Apr 3 09:41:57 2020 DistUpgraded: Fresh install DistroCodename: focal DistroVariant: ubuntu ExtraDebuggingInterest: Yes, including running git bisection searches GraphicsCard: Intel Corporation 4th Gen Core Processor Integrated Graphics Controller [8086:0416] (rev 06) (prog-if 00 [VGA controller]) Subsystem: Dell 4th Gen Core Processor Integrated Graphics Controller [1028:060d] Subsystem: Dell GK107GLM [Quadro K1100M] [1028:060d] InstallationDate: Installed on 2020-03-30 (4 days ago) InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Alpha amd64 (20200329) MachineType: Dell Inc. Dell Precision M3800 ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-21-generic root=UUID=1b7a03b4-95ff-4d1b-9897-848a0dc6f8b9 ro quiet splash vt.handoff=7 SourcePackage: xorg-server UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 05/25/2018 dmi.bios.vendor: Dell Inc. dmi.bios.version: A12 dmi.board.name: Dell Precision M3800 dmi.board.vendor: Dell Inc. dmi.board.version: A12 dmi.chassis.type: 8 dmi.chassis.vendor: Dell Inc. dmi.chassis.version: Not Specified dmi.modalias: dmi:bvnDellInc.:bvrA12:bd05/25/2018:svnDellInc.:pnDellPrecisionM3800:pvrA12:rvnDellInc.:rnDellPrecisionM3800:rvrA12:cvnDellInc.:ct8:cvrNotSpecified: dmi.product.name: Dell Precision M3800 dmi.product.sku: Dell Precision M3800 dmi.product.version: A12 dmi.sys.vendor: Dell Inc. version.compiz: compiz N/A version.libdrm2: libdrm2 2.4.100-4 version.libgl1-mesa-dri: libgl1-mesa-dri 20.0.2-1ubuntu1 version.libgl1-mesa-glx: libgl1-mesa-glx N/A version.xserver-xorg-core: xserver-xorg-core 2:1.20.7-2ubuntu2 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+git20190815-1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.16-1 ** Affects: xorg-server (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug focal ubuntu -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/1870512 Title: forced software cursor with PageFlip enabled triggers artifacts on screen To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1870512/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp