What were you trying to do that didn't work?

Trying to start "gdm" on a s390x KVM guest with virtio-gpu graphics card fails if only wayland is available (it still works with gnome-session-xsession though)
Please provide the package NVR for which bug is seen:

gnome-shell-46.2-4.el10.s390x
mutter-46.1-1.el10.s390x
gdm-46.0-3.el10.s390x
How reproducible:

100%
Steps to reproduce

virt-install --name r10test --ram=8192 --vcpus=2 --nographics --accelerate \
--network network=default,model=virtio \
-l http://.../latest-RHEL-10/compose/BaseOS/s390x/os/ \
--debug \
--console pty,target_type=sclp \
--disk /var/lib/libvirt/images/r10test.qcow2,size=12 --osinfo rhel9-unknown
Do a text mode installation of the guest to the whole disk image
Shut down the guest
Add the virtio-gpu devices, i.e. "virsh edit r10test" and add this to the "<devices>" section:
<input type='keyboard' bus='virtio'>
</input>
<input type='mouse' bus='virtio'>
</input>
<graphics type='vnc' port='-1' autoport='yes' listen='127.0.0.1'>
<listen type='address' address='127.0.0.1'/>
</graphics>
<video>
<model type='virtio' heads='1' primary='yes'/>
</video>

Start the guest again:
virsh start --console r10test
In the guest:
dnf install -y gdm
In the guest:
dnf remove -y gnome-session-xsession
In the host:
vncviewer :0
In the guest:
systemctl start gdm

Expected results

GDM login screen shows up in the VNC window
Actual results

VNC window stays black, and there are these error messages in the output of "journalctl":

gnome-shell[11448]: Cursor update failed: drmModeAddFB2 failed (No such file or directory) and drmModeAddFB cannot be used as a fallback because format
=0x34325241 (AR24).

A workaround is to disable hw cursor by adding:
MUTTER_DEBUG_DISABLE_HW_CURSORS=1 in /etc/environment,
and run systemctl restart gdm