Ansible 2.3.1 adding 'rounds=65600' to password in /etc/shadow

Hi everyone,

I just ran into a timeout when executing my unchanged playbook against
my raspi (raspi2 with debian), that I had not run on this host since
ansible 2.2 at least.

It seems ansible (or the python hash library or whoever) is adding a
rounds=656000 to the password in /etc/shadow, which takes ages on the
raspi.

# grep root /etc/shadow:
root:$6$rounds=656000$FCZN4rw4PGVBFZY5$...

Before (without the rounds in /etc/shadow)
#time sudo ls /
Root-Rechte benötigt, bitte Passwort für root eingeben:
bin boot dev etc home lib media mnt opt proc root run sbin
selinux srv sys tmp usr var

real 0m1.783s
user 0m0.544s
sys 0m0.036s

After:
time sudo ls /
Root-Rechte benötigt, bitte Passwort für root eingeben:
bin boot dev etc home lib media mnt opt proc root run sbin
selinux srv sys tmp usr var

real 1m10.551s
user 1m9.628s
sys 0m0.064s

Is there any way to avoid this?

Here is the snippet from the role:

- name: "set password for root"
  user:
    name: "root"
    password: "{{ ansible_become_pass | password_hash('sha512',
salt_for_password | default('') ) }}"
    update_password: "always"

Thanks in advance,
Johannes