Regression: Lower resolution modes on eDP are broken

[Johon Doee]

With Ubuntu Mantic, Linux 6.5 and Radeon 680M low resolution mode on hiDPI laptop displays is broken. The only resolution I can set is 3840x2400. Setting any lower resolution leads to display corruptions.

So at the moment, only one resolution can be used with hiDPI displays.

A commit to fix the issue has been released for Kernel 6.5.4 [0]. It would probably be a good idea to backport it to the Ubuntu Mantic Kernel since this is a severe regression/bug.

[0] https://gitlab.freedesktop.org/agd5f/linux/-/commit/e939dde8cd60560748fe5f1fe22c77b7cb322721

Thanks!

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 2036836

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Johon Doee (jodoee11)]

Cannot provide logs at the moment, but the bug is confirmed on freedesktop.org so I am going to set it confirmed.

[Johon Doee (jodoee11)]

@Ubuntu-devs: Is this bug going to be fixed or what's going to happen here? I cannot change display resolutions - this is a major regression!

[Johon Doee (jodoee11)]

Kernel 6.5.6 is fixing the issue: Hamza Mahfooz (1): drm/amd/display: fix the ability to use lower resolution modes on eDP

When is this fix being backported to Ubuntu's kernel? It's very disappointing that this is not addressed by the devs.