Additional finding: linux-modules-nvidia-580-open-7.0.0-28-generic was installed, but the matching 7.0.0-29 package was not. Kernel 7.0.0-29 therefore only had a DKMS NVIDIA module, which never initialized. Kernel 7.0.0-28 loads nvidia-drm normally and the external monitor works.
-------------------------------------- Additional findings / workaround: Secure Boot was enabled. On kernel 7.0.0-29, the NVIDIA DKMS module was signed with a local MOK key that was not enrolled. The kernel repeatedly logged: Loading of module with unavailable key is rejected As a result, nvidia-drm did not load and the external HDMI connector was absent. Workaround: 1. Install linux-modules-nvidia-580-open-generic-hwe-26.04 2. Enroll /var/lib/shim-signed/mok/MOK.der using mokutil 3. Reboot After enrolling the MOK key, NVIDIA 580.173.02 loaded successfully on kernel 7.0.0-29 and the external monitor returned. ------------------ The fix: sudo apt-get install -y linux-modules-nvidia-580-open-generic-hwe-26.04 sudo mokutil --import /var/lib/shim-signed/mok/MOK.der Finished by rebooting: Enroll MOK -> Continue -> Yes -> Reboot -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2163010 Title: [regression] External monitor missing on kernel 7.0.0-29, works on 7.0.0-28 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2163010/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
