My sincere apologies, I mistakenly hit enter while editing the summary and posted this bug incomplete.  I apparently can't edit the initial report now.

Description of problem:
While running with disable-user-list, after session idle causes the login screen to blank and lock, upon "unlocking" you are prompted twice for a username.

Version-Release number of selected component (if applicable):
gdm-3.8.4-28.el7_0.1.x86_64

How reproducible:
100%

Steps to Reproduce:
1.  create dconf rules to disable the user-list, and lower session idle to aide in debugging.

# echo -e "[org/gnome/desktop/session]\nidle-delay=uint32 15\n\n[org/gnome/login-screen]\ndisable-user-list=true" > /etc/dconf/db/site.d/00-test
# echo -e "/org/gnome/desktop/session/idle-delay\n/org/gnome/login-screen/disable-user-list" > /etc/dconf/db/site.d/locks/00-test-locks
# dconf update

2. Reboot and allow login screen to blank
3. Wake login screen and notice Username prompting twice.

Actual results:
User is prompted twice for username. The first prompt appears to be ignored and will accept any text.

Expected results:
User is not prompted twice, but allowed to login normally.

Additional info:
Work-around: setting idle-delay to "uint32 0" for gdm and preventing the screen from blanking allows the user to login normally.  However, the screen appears to never blank nor go to sleep.

Potentially related https://bugzilla.redhat.com/show_bug.cgi?id=1157266

Thank you for your bug report. This issue is already been tracked in our bug tracking system via bug 1109530. A fix for this issue is slated to be released in the next synchronous update (Red Hat Enterprise Linux 7.1).

*** This bug has been marked as a duplicate of bug 1109530 ***