Unable to login as normal user using gdm after upgrade to Fedora 27

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I upgraded yesterday my Fedora 26 to 27. After the update, I am unable to login as a normal user using login screen which shows up after booting. When I enter my credentials I press login, I am returned back to login screen. It's the same whether I choose gnome, gnome with xorg or gnome classic. On the other hand, it works when I log in as root.

To use a computer, I change to the other virtual console, then log in there as a normal user, and type startx which starts gnome session and works.

I tried downgrading gdm, switching to the lightdm, none of which works. What steps can I do next to troubleshoot this problem? Which logs are useful to analyze ?