Upstream GNOME recently fixed a bug that could crash gnome-shell immediately after resume: https://bugzilla.gnome.org/show_bug.cgi?id=701974 As noted here, the impact is that after resume, the password entry dialog disappears and the user is dropped into the pre-existing X session: https://bugzilla.redhat.com/show_bug.cgi?id=954054 I haven't figured out the exact trigger conditions, but this has happened to me a couple of times since switching to Fedora 19 last weekend. It does not appear to be a once-in-a-blue-moon bug. I think this needs to be tracked as a security bug because screen locking is a security feature (which is part of many security policies). -- Florian Weimer / Red Hat Product Security Team