Created attachment 360535 [details]
Description of problem:
When doing fast user switching, it pops up a window and the screen goes black until moving a mouse or clicking a key, which gives the initial login window and there is no second user account available to select.
Unable to start new display
The name org.gnome.DisplayManager was not provided by any .service files
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Ensure the 'nomodeset' in your bootloader configuration (need it for basic
X operation to suceed).
2. Ensure the file /etc/X11/xorg.conf does not exist, or is a known-good
configuration file that uses the 'radeon' driver
3. Shut your system down entirely, then start it up again
4. Create a second regular user account, if you do not already have one
5. Trigger fast switching (in a default Fedora desktop, click your name at
the top right hand corner, then select Switch User)
Error window pops up.
Fast user switching should work correctly, with no display issues on either desktop.
Created attachment 360536 [details]
Created attachment 360537 [details]
I don't think this is a driver issue, please retry with latest -ati/X server packages from rawhide.
Its more likely a gdm bug.
The testing is blocked due to the bug 522129.
we've been investigating this in the blocker bug review meeting this morning. it seems there are many reports of this type across multiple types of video hardware. closing all reports as dupes of 512944, which is the earliest report. 512944 will be marked as a release blocker.
Fedora Bugzappers volunteer triage team
*** This bug has been marked as a duplicate of bug 512944 ***