Starting Wayland-KDE on FC39

[Dave Close]

I wrote:

>Until FC39, I had only run Wayland on one of my machines, not even
>trying to bring it up on the others. Since I intensely dislike the
>graphic login, I found a way to start it from a virtual terminal like
>I normally start X11. Instead of "startx", I have a short script I call
>"startw" that contains only the single line, "/usr/bin/dbus-run-session
>/usr/bin/startplasma-wayland". This worked on FC38 and still works on
>some other of my machines with FC39.

>Now on the same machine with FC39 (upgraded with system-upgrade) this
>no longer works. Instead, it produces 248 lines of output and then
>terminates. Reviewing those lines, it appears that it is complaining
>about, 'failed to open drm device at "/dev/dri/card0"' and 'No suitable
>DRM devices have been found'. I'm not sure what device that refers
>to but there seems to be some indication that it is my display. The
>display certainly works fine for the virtual terminal I use to run
>this script, and it also works fine for X11 if I run "startx".

>Ok, so as a fallback I tried a graphic login. This reaches a completely
>blank screen and goes no further. The machine is up as I can reach it
>with SSH but the display is useless. It responds to Ctrl-Alt-Delete
>but nothing else. I can't get it to switch to a different desktop. I
>noticed that SDDM defaults to Wayland so I changed "sddm.conf" to
>include "DisplayServer=x11". The allowed the graphic login to reach
>a login page but nothing I entered there was accepted even when I
>switched to specify starting an X11 session instead of Wayland.

>It seems to me that this is unlikely to be a KDE problem, especially
>since KDE starts great under X11. I'm just hoping someone will be
>able to help me understand why this is failing. There are some online
>references to a problem with the /dev/dri/card0 device but they are
>ancient and don't seem relevant.

>This machine is intended to run an application that only works on
>Wayland (Waydroid) so at this point I'm stimied. Any suggestions
>would be very helpful.

And then as I wrote later:

>René J.V. Bertin and Duncan responded to my note. Thank you to both,
>that is great information. I'm working through the ideas now but thus
>far haven't found a solution. I won't repeat the whole exchange at this
>point, waiting until I have something to add.

Well, I followed all the suggestions and a few other ideas of my own.
I examined the permissions of nearly every system file and could find
nothing wrong. I checked all the polkit files and found nothing obvious
there, either. In the end, I took the coward's way out.

I downgraded to FC38. (Although undocumented and counter-intuitive,
"dnf system-upgrade --releasever=$previous_version" works.) Upon reboot,
Wayland starts again!

So, obviously, something is different in FC39. I'll spend some time
checking but it is no longer urgent for me. All of the other machines
I have that now run FC39 and can successfully start Wayland have AMD
Radeon graphics while this one uses an Intel 82Q35 (i915 firmware). So
it certainly looks as though the i915 firmware is the problem. I'll be
watching for updates.
-- 
         Dave Close, Compata, Irvine CA       +1 714 434 7359
       dave at compata.com              dhclose at alumni.caltech.edu
        "... all authority is capricious, but may be appeased
        by a show of zeal, unaccompanied by any real work." 
             -- Robertson Davies in "What's Bred in the Bone"