@seb128 I've removed the v4l2 loopback module. That stopped the kernel driver issue you mentioned. The problem with the artifacts persists. Now it's on my laptop screen without the external display being preset.
Note: This is only when I run on the internal intel GPU. It doesn't happen when X uses my external nvidia one. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1874543 Title: Artifacts when connected to an external 4K display Status in linux package in Ubuntu: Confirmed Bug description: I get artifacts when I connect my laptop (Lenovo X1 7th Gen) to an external 4k monitor via usb-c->DP. See the attached screenshot. This happened after I upgraded to ubuntu 20.04. ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: xorg 1:7.7+19ubuntu14 ProcVersionSignature: Ubuntu 5.4.0-26.30-generic 5.4.30 Uname: Linux 5.4.0-26-generic x86_64 ApportVersion: 2.20.11-0ubuntu27 Architecture: amd64 BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log' CasperMD5CheckResult: skip CompositorRunning: None CurrentDesktop: ubuntu:GNOME Date: Thu Apr 23 22:35:27 2020 DistUpgraded: 2020-04-23 22:04:58,240 DEBUG Running PostInstallScript: './xorg_fix_proprietary.py' DistroCodename: focal DistroVariant: ubuntu DkmsStatus: nvidia, 440.64, 5.3.0-48-generic, x86_64: installed nvidia, 440.64, 5.4.0-26-generic, x86_64: installed v4l2loopback, 0.12.3, 5.3.0-48-generic, x86_64: installed v4l2loopback, 0.12.3, 5.4.0-26-generic, x86_64: installed ExtraDebuggingInterest: Yes, including running git bisection searches GraphicsCard: Intel Corporation UHD Graphics 620 (Whiskey Lake) [8086:3ea0] (rev 02) (prog-if 00 [VGA controller]) Subsystem: Lenovo UHD Graphics 620 (Whiskey Lake) [17aa:2292] InstallationDate: Installed on 2019-10-07 (199 days ago) InstallationMedia: Ubuntu 19.04 "Disco Dingo" - Release amd64 (20190416) MachineType: LENOVO 20QDCTO1WW ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-5.4.0-26-generic root=UUID=298d5179-f5b4-410d-aafb-92630b5b48a1 ro quiet splash vt.handoff=7 SourcePackage: xorg Symptom: display UpgradeStatus: Upgraded to focal on 2020-04-23 (0 days ago) dmi.bios.date: 03/18/2020 dmi.bios.vendor: LENOVO dmi.bios.version: N2HET47W (1.30 ) dmi.board.asset.tag: Not Available dmi.board.name: 20QDCTO1WW 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:bvrN2HET47W(1.30):bd03/18/2020:svnLENOVO:pn20QDCTO1WW:pvrThinkPadX1Carbon7th:rvnLENOVO:rn20QDCTO1WW:rvrSDK0J40697WIN:cvnLENOVO:ct10:cvrNone: dmi.product.family: ThinkPad X1 Carbon 7th dmi.product.name: 20QDCTO1WW dmi.product.sku: LENOVO_MT_20QD_BU_Think_FM_ThinkPad X1 Carbon 7th dmi.product.version: ThinkPad X1 Carbon 7th dmi.sys.vendor: LENOVO version.compiz: compiz N/A version.libdrm2: libdrm2 2.4.101-2 version.libgl1-mesa-dri: libgl1-mesa-dri 20.0.4-2ubuntu1 version.libgl1-mesa-glx: libgl1-mesa-glx N/A version.xserver-xorg-core: xserver-xorg-core 2:1.20.8-2ubuntu2 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+git20200226-1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.16-1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1874543/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
