Public bug reported:
I am experiencing a kernel panic when connecting USB-C Dell monitors on
Ubuntu 24.04.3 LTS, but only on newer kernels. The problem is completely
reproducible and appears to be a regression between kernel
6.14.0-37-generic (working) and 6.17.0-14-generic (failing).
As soon as the system detects the monitors, all screens go black, the
system becomes totally frozen, and the Caps Lock LED blinks, indicating
a kernel panic. A hard shutdown is required.
The same hardware works perfectly on kernel 6.14.0-37-generic, so this
is a regression introduced in the 6.17 series.
System Information
Ubuntu Version (lsb_release -rd):
Description: Ubuntu 24.04.3 LTS
Release: 24.04
Laptop: Dell XPS 13 7390 2-in-1
CPU: Intel Core i7-1065G7
GPU: Intel Iris Plus Graphics G7 (Ice Lake)
Desktop: GNOME Shell
Kernel Versions
Working: 6.14.0-37-generic
Failing: 6.17.0-14-generic
Regression occurs between these versions.
External Monitor Setup
Primary: Dell U2721DE
27", 2560×1440
Connected via USB-C
Has built-in USB hub containing Realtek RTL8153 Gigabit Ethernet
Secondary: Dell U2421HE
24", 1920×1080
Connected via DisplayPort daisy-chain from U2721DE
Connection Path:
Laptop USB-C → Dell U2721DE → DisplayPort → Dell U2421HE
The issue happens even with the secondary monitor disconnected.
Steps to Reproduce
Boot Ubuntu using kernel 6.17.0-14-generic
Log in to the desktop
Connect USB-C cable from laptop to Dell U2721DE
System instantly crashes
Expected Behavior
Monitor should be detected normally
System remains stable
Displays stay active
This is exactly what happens on 6.14.0-37-generic.
Actual Behavior (Failing Kernel 6.17.0-14-generic)
All screens immediately turn black
Laptop’s internal display also shuts off
System is completely frozen
Caps Lock LED blinks → kernel panic
Hard power-off required
ProblemType: Bug
DistroRelease: Ubuntu 24.04
Package: linux-image-6.17.0-14-generic 6.17.0-14.14~24.04.1
ProcVersionSignature: Ubuntu 6.17.0-14.14~24.04.1-generic 6.17.9
Uname: Linux 6.17.0-14-generic x86_64
ApportVersion: 2.28.1-0ubuntu3.8
Architecture: amd64
CasperMD5CheckResult: pass
CurrentDesktop: ubuntu:GNOME
Date: Sun Feb 8 07:22:30 2026
InstallationDate: Installed on 2026-01-30 (9 days ago)
InstallationMedia: Ubuntu 24.04.3 LTS "Noble Numbat" - Release amd64
(20250805.1)
ProcEnviron:
LANG=en_US.UTF-8
PATH=(custom, no user)
SHELL=/bin/bash
TERM=xterm-256color
XDG_RUNTIME_DIR=<set>
SourcePackage: linux-signed-hwe-6.17
UpgradeStatus: No upgrade log present (probably fresh install)
** Affects: linux-signed-hwe-6.17 (Ubuntu)
Importance: Undecided
Status: New
** Tags: amd64 apport-bug noble wayland-session
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https://bugs.launchpad.net/bugs/2141225
Title:
Kernel panic when connecting USB-C Dell monitors on Ubuntu kernel
6.17.0-14-generic
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