Builtin laptop screen no longer works in X11 after Ubuntu 22.04 LTS upgrade

Graphics / Linux Linux
1

I run Ubuntu 22.04 LTS (to please employer) with Kubuntu backports PPA (to have KDE Plasma X11). It’s a strange arrangement but it’s been working well for 18 months.

My laptop has an AMD Radeon APU and a dedicated GeForce RTX 3060 Mobile. I always work on my desk, so laptop is connected to an external monitor (USB-C to DisplayPort cable) and that monitor is connected to a second external monitor (HDMI and Multi-Stream Transport). It’s a work laptop used for coding. It has secure boot and an encrypted LVM volume.

After installing Ubuntu upgrades, the laptop builtin screen no longer works in GUI mode. I see startup messages, but I don’t get to see SDDM. The two external monitors work normally, though. But if I don’t connect external monitors, I cannot use X11. Neither Plasma displays settings nor Nvidia app seem to detect that the screen exists at all.

The update included a 6.2 to 6.5 kernel upgrade, as well as some nvidia packages. I’ve been trying a number of things that didn’t solve the problem (and in some cases made it worse):

  • Upgrade drivers from 525 to 535. Issue persists.
  • Use Grub menu to boot with backup 6.2 kernel. Issue persists.
  • Attempt to uninstall 6.5 and revert to 6.2. I didn’t succeed.
  • Change UEFI settings from “Switchable Graphics” to “Discrete Graphics”. All three screens got blank.

Here’s my nvidia-bug-report.sh output:

nvidia-bug-report.log.gz (409.2 KB)

Here’s an excerpt from /var/log/apt/history.log (upgrade happened on 2024-01-10 16:43:20):

history.log (11.4 KB)

Sorry if this has been asked before, but I’m done with running random commands from forum posts I don’t fully understand.

2

Please delete /etc/X11/xorg.conf

1 Like
3

Thank you, after deleting /etc/X11/xorg.conf the builtin pane works again!

And, sorry, I had totally forgotten the first issue I had experimented right after the kernel upgrade (it’s been a tough week), which is that the laptop screen only works at native resolution (2560x1600) but, in order to match the actual display size of external monitors, I need to lower it (1680x1050). But all other resolutions cause flickering white noise. I understand that’s a different problem, I’m not sure if I need to provide further information.

4

The internal display is driven by your amd gpu, so I guess you need to open a bug report for the amdgpu driver. You could also provide a new nvidia-bug-report.log right after boot so I could check if there are any errors regarding that.

5

Here you are:

nvidia-bug-report.log.gz (361.9 KB)

If you don’t see anything wrong, at least I know where to investigate further.

6

No obvious errors or warnings visible. Since all resolutions other than the display’s native one are virtual, scaled resolutions created by the amdgpu kernel driver, I guess its scaling code is at fault. No way around it but opening a bug report with the amdgpu driver.
https://gitlab.freedesktop.org/drm/amd/-/issues/?sort=created_date&state=opened&first_page_size=20

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