Public bug reported: Whenever I plug an external monitor (Dell P2720DC) on my ThinkPad X1 (8th gen.) with Ubuntu 20.04, it is not directly recognized. I need to reboot the system so that it can find the monitor. Here is an extract of dmesg:
[87389.923632] usb 1-5: new high-speed USB device number 33 using xhci_hcd [87390.072891] usb 1-5: New USB device found, idVendor=413c, idProduct=8442, bcdDevice= 1.00 [87390.072897] usb 1-5: New USB device strings: Mfr=0, Product=0, SerialNumber=1 [87390.072901] usb 1-5: SerialNumber: E9021071FBE1 [87390.073934] hub 1-5:1.0: USB hub found [87390.074047] hub 1-5:1.0: 6 ports detected [87390.367780] usb 1-5.5: new high-speed USB device number 34 using xhci_hcd [87390.472473] usb 1-5.5: New USB device found, idVendor=0451, idProduct=82ff, bcdDevice= 2.00 [87390.472479] usb 1-5.5: New USB device strings: Mfr=0, Product=0, SerialNumber=0 [87390.475022] hid-generic 0003:0451:82FF.0014: hiddev0,hidraw1: USB HID v1.11 Device [HID 0451:82ff] on usb-0000:00:14.0-5.5/input0 ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: xorg 1:7.7+19ubuntu14 ProcVersionSignature: Ubuntu 5.4.0-47.51-generic 5.4.55 Uname: Linux 5.4.0-47-generic x86_64 ApportVersion: 2.20.11-0ubuntu27.8 Architecture: amd64 BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log' CasperMD5CheckResult: skip CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins' CompositorRunning: None CurrentDesktop: Unity Date: Wed Sep 16 09:40:10 2020 DistUpgraded: Fresh install DistroCodename: focal DistroVariant: ubuntu EcryptfsInUse: Yes ExtraDebuggingInterest: Yes GraphicsCard: Intel Corporation UHD Graphics [8086:9b41] (rev 02) (prog-if 00 [VGA controller]) Subsystem: Lenovo UHD Graphics [17aa:22be] InstallationDate: Installed on 2020-08-24 (22 days ago) InstallationMedia: Ubuntu 20.04.1 LTS "Focal Fossa" - Release amd64 (20200731) MachineType: LENOVO 20U9004PFR ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-47-generic root=UUID=4a93b148-f388-4849-9a18-9e0e4d32c97a ro quiet splash vt.handoff=7 SourcePackage: xorg Symptom: display UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 07/01/2020 dmi.bios.vendor: LENOVO dmi.bios.version: N2WET19W (1.09 ) dmi.board.asset.tag: Not Available dmi.board.name: 20U9004PFR 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:bvrN2WET19W(1.09):bd07/01/2020:svnLENOVO:pn20U9004PFR:pvrThinkPadX1CarbonGen8:rvnLENOVO:rn20U9004PFR:rvrSDK0J40697WIN:cvnLENOVO:ct10:cvrNone: dmi.product.family: ThinkPad X1 Carbon Gen 8 dmi.product.name: 20U9004PFR dmi.product.sku: LENOVO_MT_20U9_BU_Think_FM_ThinkPad X1 Carbon Gen 8 dmi.product.version: ThinkPad X1 Carbon Gen 8 dmi.sys.vendor: LENOVO version.compiz: compiz N/A version.libdrm2: libdrm2 2.4.101-2 version.libgl1-mesa-dri: libgl1-mesa-dri 20.0.8-0ubuntu1~20.04.1 version.libgl1-mesa-glx: libgl1-mesa-glx 20.0.8-0ubuntu1~20.04.1 version.xserver-xorg-core: xserver-xorg-core 2:1.20.8-2ubuntu2.4 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 ** Affects: xorg (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug focal thinkpadx1 ubuntu usbc ** Tags added: thinkpadx1 usbc -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1895794 Title: Plugging an external monitor on USB-C port does not show up. Need to reboot each time To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1895794/+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