Rasp 3B+, manjaro 19.06 with lxqt,stuck when booting

When i booted my rasp 3B+ the first time, everything was okay. But after a while it turns to an tty and show a line at the below, where "switching to vc4drmfb from simple" was read. Then i ignore the signal and reboot it. Finally, it stuck at the booting.
After that, i just find This . I successfully put vc4 into blacklist and then reboot. What came to me is
[ok]started NetWork Manager Script Dispatcher Service
IPv6: ADDRCONF(NETDEV_CHANGE): wln0: link becomes ready
and stuck again!!!
help me!Thanks!!!