Description of problem: This seems to happen in a VM when I enable automatic login in GNOME. On boot, instead of gdm I see only a black screen. I can switch to other TTYs and log in using text mode. There is spice-vdagentd traceback in journal, I suspect that's what kills gdm. When I try to reboot, I have to wait 90 seconds before systemd kills some processes. Version-Release number of selected component: spice-vdagent-0.16.0-1.fc23 Additional info: reporter: libreport-2.6.2 backtrace_rating: 4 cmdline: /usr/sbin/spice-vdagentd crash_function: __open_memstream executable: /usr/sbin/spice-vdagentd global_pid: 745 kernel: 4.2.2-300.fc23.x86_64 runlevel: N 5 type: CCpp uid: 0 Truncated backtrace: Thread no. 1 (5 frames) #3 __open_memstream at memstream.c:85 #4 __vsyslog_chk at ../misc/syslog.c:167 #5 __syslog_chk at ../misc/syslog.c:129 #6 update_active_session_connection at src/vdagentd.c:645 #7 main_loop at src/vdagentd.c:881
Created attachment 1080660 [details] File: backtrace
Created attachment 1080661 [details] File: cgroup
Created attachment 1080662 [details] File: core_backtrace
Created attachment 1080663 [details] File: dso_list
Created attachment 1080664 [details] File: environ
Created attachment 1080665 [details] File: exploitable
Created attachment 1080666 [details] File: limits
Created attachment 1080667 [details] File: maps
Created attachment 1080668 [details] File: mountinfo
Created attachment 1080669 [details] File: namespaces
Created attachment 1080670 [details] File: open_fds
Created attachment 1080671 [details] File: proc_pid_status
Created attachment 1080672 [details] File: var_log_messages
Created attachment 1080683 [details] full system journal This is full journal from an attempt to boot in a VM with GDM autologin enabled. 14:10:21 timestamp is roughly the time when I see only black screen instead of gdm and then I switch to tty2 and try to reboot, which takes 90 seconds.
This problem is fixed by this update: https://bodhi.fedoraproject.org/updates/FEDORA-2015-a7f21b1850 Proposing as a FinalFreezeException, this will allow autologin in VMs without updating your system first. If this is not stable, people will have troubles disabling autologin to get working graphics again (you need to edit /etc/gdm/custom.conf).
The bodhi update has been pushed to stable, closing.