- name: set grub timeout
  lineinfile:
    path: /etc/default/grub
    regexp: ^GRUB_TIMEOUT=
    line: 'GRUB_TIMEOUT={{ grub_timeout }}'
  register: grub_timeout_line

- name: set kernel cmdline
  lineinfile:
    path: /etc/default/grub
    regexp: ^GRUB_CMDLINE_LINUX=
    line: 'GRUB_CMDLINE_LINUX="{{ grub_cmdline }}"'
  when: grub_cmdline is defined
  register: grub_cmdline_line

- name: rebuild grub config
  command: grub2-mkconfig -o /boot/grub2/grub.cfg
  when: grub_timeout_line.changed or grub_cmdline_line.changed

- name: warn if reboot needed
  debug:
    msg: A reboot is required for changes to kernel cmdline to take effect.
  when: grub_cmdline_line.changed