I have found a fix. First I tried adding "nouveau.modeset=0" to bootflags, which got me to boot but no greeter. sddm appeared to be happily running but it failed to start the display server restarting it did not help "startx" worked, which gave me hope
It appeared the session "seat" had been determined by systemd to have "CanGraphical" false Then I found this: https://github.com/mikhailnov/systemd/commit/c00bf275fdfbad3a9db8934b5e266b6abbdb8443 There's a heuristic hack which sets CanGraphical when the kernel starts w/o graphics, but only if this is done via "nomodeset" rather than the driver-specific ".modeset" flags So I just added "nomodeset" to boot flags, and now not only does 6.5.0-28 boot and land at a working greeter again, but all the weird sddm graphics bugs i'd been encountering since 6.5 are gone. Hope this helps someone else... And maybe this kernel issue will get fixed, some day -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1788044 Title: task kworker blocked for more than 120 seconds nouveau To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1788044/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs