`su root` failed with `su: cannot set groups: Operation not permitted`

[exfly]

./run_debian_x86_64.sh run

su root
Password: 123
su: cannot set groups: Operation not permitted

su root
Password: xxx
su: Authentication failure

[exfly]

workround: ./run_debian_x86_64.sh run and login as root

[runninglinuxkernel]

user：root
password: 123