Public bug reported:

7.0.0-28-generic: internal panel remains extremely dim
7.0.0-22-generic: works normally

External monitors are unaffected.

On the bad kernel:
/sys/class/backlight/intel_backlight/brightness = 1023
actual_brightness = 1023
max_brightness = 1023
bl_power = 0

Writing to brightness directly can reduce brightness further, but not
increase it beyond 1023.

Previously systemd-backlight had saved brightness 36001, while the bad
kernel exposes a maximum of 1023.

journalctl has the following entries relevant to display stuff:
Jul 18 12:33:46 hostname kernel: ACPI: bus type drm_connector registered
Jul 18 12:33:46 hostname kernel: serio: i8042 AUX port at 0x60,0x64 irq 12
Jul 18 12:33:46 hostname kernel: simple-framebuffer simple-framebuffer.0: [drm] 
Registered 1 planes with drm panic
Jul 18 12:33:46 hostname kernel: [drm] Initialized simpledrm 1.0.0 for 
simple-framebuffer.0 on minor 0
Jul 18 12:33:46 hostname kernel: simple-framebuffer simple-framebuffer.0: [drm] 
fb0: simpledrmdrmfb frame buffer device
Jul 18 12:33:46 hostname systemd[1]: [email protected] - Load Kernel Module 
drm skipped, unmet condition check ConditionKernelModuleLoaded=!drm
Jul 18 12:33:48 hostname kernel: i915 0000:00:02.0: [drm] Found coffeelake 
(device ID 3e9b) integrated display version 9.00 stepping N/A
Jul 18 12:33:48 hostname kernel: i915 0000:00:02.0: [drm] VT-d active for gfx 
access
Jul 18 12:33:48 hostname kernel: [drm] [nvidia-drm] [GPU ID 0x00000100] Loading 
driver
Jul 18 12:33:48 hostname kernel: i915 0000:00:02.0: vgaarb: deactivate vga 
console
Jul 18 12:33:48 hostname kernel: i915 0000:00:02.0: [drm] Using Transparent 
Hugepages
Jul 18 12:33:48 hostname kernel: i915 0000:00:02.0: vgaarb: VGA decodes 
changed: olddecodes=io+mem,decodes=none:owns=io+mem
Jul 18 12:33:48 hostname kernel: i915 0000:00:02.0: [drm] Finished loading DMC 
firmware i915/kbl_dmc_ver1_04.bin (v1.4)
Jul 18 12:33:48 hostname kernel: mei_hdcp 
0000:00:16.0-b638ab7e-94e2-4ea2-a552-d1c54b627f04: bound 0000:00:02.0 (ops 
i915_hdcp_ops [i915])
Jul 18 12:33:48 hostname kernel: i915 0000:00:02.0: [drm] Registered 3 planes 
with drm panic
Jul 18 12:33:48 hostname kernel: [drm] Initialized i915 1.6.0 for 0000:00:02.0 
on minor 1
Jul 18 12:33:48 hostname kernel: fbcon: i915drmfb (fb0) is primary device
Jul 18 12:33:48 hostname kernel: i915 0000:00:02.0: [drm] fb0: i915drmfb frame 
buffer device
Jul 18 12:33:49 hostname kernel: snd_hda_intel 0000:00:1f.3: bound 0000:00:02.0 
(ops intel_audio_component_bind_ops [i915])
Jul 18 12:33:49 hostname kernel: [drm] Initialized nvidia-drm 0.0.0 for 
0000:01:00.0 on minor 2
Jul 18 12:33:49 hostname kernel: nvidia 0000:01:00.0: [drm] Cannot find any 
crtc or sizes

ProblemType: Bug
DistroRelease: Ubuntu 26.04
Package: linux-image-7.0.0-28-generic 7.0.0-28.28
ProcVersionSignature: Ubuntu 7.0.0-28.28-generic 7.0.12
Uname: Linux 7.0.0-28-generic x86_64
ApportVersion: 2.34.0-0ubuntu2
Architecture: amd64
AudioDevicesInUse:
 USER        PID ACCESS COMMAND
 /dev/snd/controlC1:  rene       2375 F.... wireplumber
 /dev/snd/controlC0:  rene       2375 F.... wireplumber
 /dev/snd/seq:        rene       2371 F.... pipewire
CasperMD5CheckResult: unknown
CurrentDesktop: KDE
Date: Sat Jul 18 12:35:33 2026
InstallationDate: Installed on 2026-06-20 (28 days ago)
InstallationMedia: Kubuntu 26.04 "Resolute Raccoon" - Release amd64 (20260423)
MachineType: Dell Inc. G5 5590
ProcFB: 0 i915drmfb
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-7.0.0-28-generic 
root=UUID=f7fa5d66-47e3-49b6-b017-d62f3f9e602b ro rootflags=subvol=@ quiet 
cryptdevice=UUID=746ff933-7259-443d-89a5-45702252db53:luks-746ff933-7259-443d-89a5-45702252db53
 root=/dev/mapper/luks-746ff933-7259-443d-89a5-45702252db53 splash
PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No 
PulseAudio daemon running, or not running as session daemon.
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 03/15/2022
dmi.bios.release: 1.19
dmi.bios.vendor: Dell Inc.
dmi.bios.version: 1.19.0
dmi.board.name: 0CNDTP
dmi.board.vendor: Dell Inc.
dmi.board.version: A04
dmi.chassis.type: 10
dmi.chassis.vendor: Dell Inc.
dmi.modalias: 
dmi:bvnDellInc.:bvr1.19.0:bd03/15/2022:br1.19:svnDellInc.:pnG55590:pvr:rvnDellInc.:rn0CNDTP:rvrA04:cvnDellInc.:ct10:cvr:sku08EA:pfaGSeries:
dmi.product.family: GSeries
dmi.product.name: G5 5590
dmi.product.sku: 08EA
dmi.sys.vendor: Dell Inc.

** Affects: linux (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: amd64 apport-bug resolute wayland-session

-- 
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/2161182

Title:
  Internal Intel eDP panel is extremely dim after upgrading the kernel.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2161182/+subscriptions


-- 
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs

Reply via email to