I updated Rawhide today, rebooted, and found I could no longer login through GDM. It reports 'authentication failure', even though I'm typing the right password for my user. (Yes, I really, really am). I can log in through a console and run 'startx' just fine.

journalctl -a shows:

Jul 04 19:32:35 adam.localdomain unix_chkpwd[1653]: password check failed for user (adamw)
Jul 04 19:32:35 adam.localdomain gdm-password][1647]: pam_unix(gdm-password:auth): authentication failure; logname=(unknown) uid=0 euid=0 tty=:0 ruser= rhost=  user=adamw
Jul 04 19:33:12 adam.localdomain gdm[588]: GLib-GIO: g_dbus_method_invocation_return_value_internal: assertion 'G_IS_DBUS_METHOD_INVOCATION (invocation)' failed
Jul 04 19:33:12 adam.localdomain unix_chkpwd[1661]: password check failed for user (adamw)
Jul 04 19:33:12 adam.localdomain gdm-password][1654]: pam_unix(gdm-password:auth): authentication failure; logname=(unknown) uid=0 euid=0 tty=:0 ruser= rhost=  user=adamw
Jul 04 19:33:22 adam.localdomain unix_chkpwd[1668]: password check failed for user (adamw)
Jul 04 19:33:22 adam.localdomain gdm-password][1663]: pam_unix(gdm-password:auth): authentication failure; logname=(unknown) uid=0 euid=0 tty=:0 ruser= rhost=  user=adamw

(that's three attempts).

When logging in to a VT I note this error:

Jul 04 19:35:06 adam.localdomain systemd[1418]: Failed at step PAM spawning /usr/lib/systemd/systemd: Operation not permitted

I haven't checked yet if this is an SELinux thing, guess I should.