[Bug 2136103] Re: [i915] Limited resolutions in monitors connected via USB hub when using 6.8.0-90.91-generic

Hi, thanks for reporting a kernel regression!

Do you know the version of the LTS kernel which was last working? If you
reinstall that older kernel and boot into it, does the issue go away?
This would help us narrow down what patches to look at.

Trying an upstream stable kernel would also tell us if the regression is
on Ubuntu's side or upstream. Could you try to reproduce the problem
with this mainline kernel: https://kernel.ubuntu.com/mainline/v6.6.119/
? A guide to installing mainline kernel packages is available at
https://wiki.ubuntu.com/Kernel/MainlineBuilds

** Changed in: linux (Ubuntu Noble)
Assignee: (unassigned) => Ian Whitfield (ijwhitfield)

--
You received this bug notification because you are subscribed to linux
in Ubuntu.
Matching subscriptions: Bgg, Bmail, Nb
https://bugs.launchpad.net/bugs/2136103

Title:
[i915] Limited resolutions in monitors connected via USB hub when
using 6.8.0-90.91-generic

Status in linux package in Ubuntu:
Invalid
Status in linux-hwe-6.14 package in Ubuntu:
Invalid
Status in linux source package in Noble:
Triaged
Status in linux-hwe-6.14 source package in Noble:
Invalid

Bug description:
Connecting a second monitor through USB hub limits resolution to
1920x1080. Last week this same monitor, connecting to the same USB hub
(UGREEN Revodock 10-in-1) was displaying 3440x1440 without problem.

ProblemType: Bug
DistroRelease: Ubuntu 24.04
Package: xorg 1:7.7+23ubuntu3
ProcVersionSignature: Ubuntu 6.8.0-90.91-generic 6.8.12
Uname: Linux 6.8.0-90-generic x86_64
ApportVersion: 2.28.1-0ubuntu3.8
Architecture: amd64
BootLog: Error: [Errno 13] S'ha denegat el permís: '/var/log/boot.log'
CasperMD5CheckResult: unknown
CompositorRunning: None
CurrentDesktop: GNOME
Date: Mon Dec 15 10:56:58 2025
DistUpgraded: Fresh install
DistroCodename: noble
DistroVariant: ubuntu
DkmsStatus:
virtualbox/7.0.16, 6.8.0-88-generic, x86_64: installed
virtualbox/7.0.16, 6.8.0-90-generic, x86_64: installed
ExtraDebuggingInterest: Yes
GraphicsCard:
Intel Corporation Alder Lake-UP3 GT2 [Iris Xe Graphics] [8086:46a8] (rev 0c) (prog-if 00 [VGA controller])
Subsystem: Lenovo Alder Lake-UP3 GT2 [Iris Xe Graphics] [17aa:50a6]
InstallationDate: Installed on 2024-03-13 (642 days ago)
InstallationMedia: Ubuntu 23.10.1 "Mantic Minotaur" - Release amd64 (20231016.1)
MachineType: LENOVO 21B3000KSP
ProcEnviron:
LANG=ca_ES.UTF-8
PATH=(custom, no user)
SHELL=/bin/bash
TERM=xterm-256color
XDG_RUNTIME_DIR=<set>
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-6.8.0-90-generic root=UUID=8fb7af86-3f88-4f8b-b558-0055afa35cb6 ro quiet splash vt.handoff=7
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 06/11/2025
dmi.bios.release: 1.29
dmi.bios.vendor: LENOVO
dmi.bios.version: R1UET52W (1.29 )
dmi.board.asset.tag: Not Available
dmi.board.name: 21B3000KSP
dmi.board.vendor: LENOVO
dmi.board.version: SDK0T76538 WIN
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.ec.firmware.release: 1.17
dmi.modalias: dmi:bvnLENOVO:bvrR1UET52W(1.29):bd06/11/2025:br1.29:efr1.17:svnLENOVO:pn21B3000KSP:pvrThinkPadL13Gen3:rvnLENOVO:rn21B3000KSP:rvrSDK0T76538WIN:cvnLENOVO:ct10:cvrNone:skuLENOVO_MT_21B3_BU_Think_FM_ThinkPadL13Gen3:
dmi.product.family: ThinkPad L13 Gen 3
dmi.product.name: 21B3000KSP
dmi.product.sku: LENOVO_MT_21B3_BU_Think_FM_ThinkPad L13 Gen 3
dmi.product.version: ThinkPad L13 Gen 3
dmi.sys.vendor: LENOVO
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.122-1~ubuntu0.24.04.2
version.libgl1-mesa-dri: libgl1-mesa-dri 25.0.7-0ubuntu0.24.04.2
version.libgl1-mesa-glx: libgl1-mesa-glx N/A
version.xserver-xorg-core: xserver-xorg-core 2:21.1.12-1ubuntu1.5
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:22.0.0-1build1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20210115-1build1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.17-2ubuntu0.1

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2136103/+subscriptions