Fedora 預設root帳號是無法登入X window

#vim /etc/pam.d/gdm

#%PAM-1.0
auth    [success=done ignore=ignore default=bad] pam_selinux_permit.so
#auth   required  pam_succeed_if.so user != root quiet 

vim /etc/pam.d/gdm-password
# auth required pam_succeed_if.so user !=root quiet