3840x2160@60Hz missing from connector's mode list even though it's explicitly declared in the EDID

NVIDIA Open GPU Kernel Modules Version

595.71.05

Please confirm this issue does not happen with the proprietary driver (of the same version). This issue tracker is only for bugs specific to the open kernel driver.

• I confirm that this does not happen with the proprietary driver package.

Operating System and Version

Nobara Linux 43 (Fedora 43 base)

Kernel Release

7.0.11-200.nobara.fc43.x86_64

Please confirm you are running a stable release kernel (e.g. not a -rc). We do not accept bug reports for unreleased kernels.

• I am running on a stable kernel release.

Hardware: GPU

RTX 4080 SUPER

Describe the bug

This projector's stock, unmodified EDID declares 3840x2160@60Hz twice — as VIC 97 in the Video Data Block, and as a full Detailed Timing Descriptor (594MHz). Despite that, KDE Plasma on Wayland caps DP-3 at 3840x2160@30Hz; no 50/60Hz 4K mode ever shows up. The same projector, cable, and adapter get 4K60 immediately on Windows, so it's not a hardware/bandwidth issue — something in the Wayland/KMS path is dropping a mode the EDID already declares.

To Reproduce

• Connect a 4K display whose EDID declares VIC 97 (3840x2160@60Hz) as both a VIC and an explicit DTD.
• Boot Plasma Wayland with the NVIDIA driver; check kscreen-doctor -o — 4K60 isn't in the mode list (caps at 30Hz).
• Confirm Windows gets 4K60 through the identical cable/adapter — rules out hardware.
• Patched the EDID's legacy "Maximum TMDS clock" byte (300→600MHz, matching the HDMI Forum VSDB) in case that mismatch was the cause, loaded via drm.edid_firmware= at boot, confirmed via dmesg it was active — mode still missing.

Bug Incidence

Always

nvidia-bug-report.log.gz

nvidia-bug-report.log.gz

More Info

595.71.05 doesn't ship a proprietary kernel module (NVIDIA dropped that option around driver 590 for this GPU generation), so I couldn't cross-check against the closed driver.

The usual fix for "EDID says it exists but the driver won't allow it" is Option "ModeValidation" "AllowNonEdidModes" — but that's X11/xorg.conf-only as far as I can tell, no Wayland/kernel-module equivalent I could find. Can't test X11 either since Nobara 43 dropped it entirely.

Happy to attach the raw EDID binary if useful.

Start by reproducing the issue with the reported NVIDIA driver, Plasma Wayland setup, and an EDID containing VIC 97 and the 594MHz detailed timing; inspect kscreen-doctor -o and the attached nvidia-bug-report.log.gz. Compare the active EDID and connector mode list, and determine what prevents 3840x2160@60Hz from appearing. Done means the mode is exposed for this configuration without relying on the X11-only workaround.