What errors occur reasonable?

[joshita]

Hi everybody, I installed Arch Linux ARM on my Raspberry Pi model B+ and after a system upgrade yesterday using pacman -Syu, I can't login to Pi using ssh anymore. I always use root user to login and after the system upgrade, the terminal prompt "Permission denied, please try again", which I think means that my password was incorrect, but I'm so sure that my provided password is correct because I do not remember it in my head but copy it out from a file. So I was so confused and I tried following methods and they all didn't work:
(1) plug the Raspberry Pi TF card to another Ubuntu PC, edit the /etc/shadow file on the TF card, delete the password field of the root user, to make it became:

[graysky]

Connecting over ssh as root has been disabled for a while now as far as I know. This is why an alarm user is created in the default build.