Comment # 15 on bug 1198545 from Nick Singer

I face the same issue on a GTX1060 with G06 and the most recent kernel
installed.
The symptoms are the same as described by Sotir Danailov. What usually helps
for me is restarting sddm - afterwards the login screen appears.
Here is what the journal shows:

Jul 05 19:52:34 heimdall kernel: [drm:drm_new_set_master [drm]] *ERROR*
[nvidia-drm] [GPU ID 0x00000100] Failed to grab modeset ownership
Jul 05 19:52:34 heimdall kernel: [drm:drm_new_set_master [drm]] *ERROR*
[nvidia-drm] [GPU ID 0x00000100] Failed to grab modeset ownership
Jul 05 19:52:34 heimdall kernel: [drm:drm_new_set_master [drm]] *ERROR*
[nvidia-drm] [GPU ID 0x00000100] Failed to grab modeset ownership
Jul 05 19:52:35 heimdall sddm[1010]: Setting default cursor
Jul 05 19:52:35 heimdall kernel: [drm:drm_new_set_master [drm]] *ERROR*
[nvidia-drm] [GPU ID 0x00000100] Failed to grab modeset ownership
Jul 05 19:52:35 heimdall kernel: [drm:drm_new_set_master [drm]] *ERROR*
[nvidia-drm] [GPU ID 0x00000100] Failed to grab modeset ownership
Jul 05 19:52:35 heimdall kernel: [drm:drm_new_set_master [drm]] *ERROR*
[nvidia-drm] [GPU ID 0x00000100] Failed to grab modeset ownership
Jul 05 19:52:35 heimdall sddm[1010]: Running display setup script 
"/usr/etc/X11/xdm/Xsetup"
Jul 05 19:52:35 heimdall sddm[1010]: Display server started.
Jul 05 19:52:35 heimdall sddm[1010]: Socket server starting...
Jul 05 19:52:35 heimdall sddm[1010]: Socket server started.
Jul 05 19:52:35 heimdall sddm[1010]: Loading theme configuration from
"/usr/share/sddm/themes/breeze-openSUSE/theme.conf"
Jul 05 19:52:35 heimdall sddm[1010]: Greeter starting...
Jul 05 19:52:35 heimdall sddm-helper[1192]: [PAM] Starting...
Jul 05 19:52:35 heimdall sddm-helper[1192]: [PAM] Authenticating...
Jul 05 19:52:35 heimdall sddm-helper[1192]: [PAM] returning.
Jul 05 19:52:35 heimdall systemd[1]: Created slice User Slice of UID 465.
Jul 05 19:52:35 heimdall systemd[1]: Starting User Runtime Directory
/run/user/465...
Jul 05 19:52:35 heimdall systemd-logind[692]: New session 2 of user sddm.

I will try the workaround with "options nvidia-drm modeset=0" and report back
but please assume the regression isn't fixed by more recent versions of
driver/kernel.