Hello,
On 8/6/2026 5:13 PM, [email protected] wrote:
Hello Linux kernel and Intel graphics developers,
I would like to report a kernel regression affecting the internal
display brightness on my Dell Latitude 7390 laptop.
After upgrading from Linux kernel 6.14.x to Linux kernel 7.x, the
internal laptop display becomes extremely dim immediately after boot.
The system continues to run normally, but the brightness level becomes
almost unusable.
Booting back into Linux kernel 6.14.x restores normal display brightness.
Thank you for the report.
Can you please file a bug using [1]?
==
Chaitanya
[1] https://drm.pages.freedesktop.org/intel-docs/how-to-file-i915-bugs.html
Hardware information:
Laptop:
Dell Latitude 7390
CPU:
Intel Core i7-8650U
GPU:
Intel UHD Graphics 620
PCI ID: 8086:5917
Graphics driver:
i915
Display:
Chi Mei Innolux 1920x1080 eDP panel
BIOS:
Dell version 1.44.0
Operating systems tested:
*
Ubuntu 24.04.4 LTS
*
Linux Mint 22.2 (based on Ubuntu 24.04)
The same issue happens on both distributions.
Working kernel:
6.14.0-29-generic
Problematic kernel:
7.x
Steps to reproduce:
1.
Install Ubuntu 24.04 or Linux Mint 22.2.
2.
Update the system to kernel 7.x.
3.
Reboot.
4.
The internal display becomes extremely dim.
5.
Boot kernel 6.14.x.
6.
Display brightness works normally again.
Additional information:
*
Secure Boot is disabled.
*
The issue is reproducible.
*
The system remains usable except for the display brightness problem.
*
The regression appears between kernel 6.14 and kernel 7.x.
*
The graphics driver in use is Intel i915.
This may be related to Intel i915 backlight handling or eDP panel
initialization.
I can provide dmesg logs and additional debugging information if required.
Thank you for your help.
Best regards,
PoL
