Issues with system/kernel/tasks/set-kernel-opts.yml in latest build

Bug reports
1

Version:

revision: 6320e157a22f47d0dad42f84e8ee58b06aa5db3f
timestamp: 1774653761
ver_maj: 3
ver_min: 2
ver_patch: 0
ver_pre: 6320e157a-dirty
dirty: true
debug: false

Fresh install on Rocky 8 failed configuring the Kernel via Ansible.

fatal: [localhost]: FAILED! => 
  msg: 'Unexpected templating type error occurred on ({{ (state | default(''present'') == ''absent'') | ternary(''Removing'', ''Adding'') }} {{ item.key }}{{ (state | default(''present'') == ''absent'') | ternary('''', '' => '' + item.value) }}): must be str, not NoneType'

Fixing the loop solved that error:

loop_control:
  label: "{{ (state | default('present') == 'absent') | ternary('Removing', 'Adding') }} {{ item.key }}{{ (state | default('present') == 'absent') | ternary('', ' => ' + (item.value | string)) }}"

Then it failed with a grub issue, turns out the regex / replace was corrupting line 6 of /etc/default/grub

fatal: [localhost]: FAILED! => changed=true 
  cmd:
  - /usr/sbin/grub2-mkconfig
  - -o
  - /etc/grub2.cfg
  delta: '0:00:00.195315'
  end: '2026-03-29 19:34:24.767710'
  msg: non-zero return code
  rc: 2
  start: '2026-03-29 19:34:24.572395'
  stderr: '/etc/default/grub: line 7: unexpected EOF while looking for matching `"'''
  stderr_lines: <omitted>
  stdout: ''
  stdout_lines: <omitted>

$] cat /etc/default/grub 

GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)"
GRUB_DEFAULT=saved
GRUB_DISABLE_SUBMENU=true
GRUB_TERMINAL_OUTPUT="console"
GRUB_CMDLINE_LINUX="resume=UUID=c613f83b-c875-487f-9039-b6c4d623468d rootflags=usrquota,grpquota,prjquota" systemd.unified_cgroup_hierarchy=1"
GRUB_DISABLE_RECOVERY="true"
GRUB_ENABLE_BLSCFG=true

Line 6 should be:
GRUB_CMDLINE_LINUX="resume=UUID=c613f83b-c875-487f-9039-b6c4d623468d rootflags=usrquota,grpquota,prjquota systemd.unified_cgroup_hierarchy=1"

The regex inserted systemd.unified_cgroup_hierarchy=1 outside the closing quote instead of inside it.

At this point, I’m not a regex expert and brought in Claude to assist. While this is by no means a perfect solution, it did allow my installation to complete.

- name: Set kernel flags (strip existing value)
  replace:
    path: "{{ kernel_boot_cmdline }}"
    regexp: '{{ regex_preamble }}\s+{{ item.key | regex_escape }}=[^"''\s]+'
    replace: '\1'
  loop_control:
    label: "Stripping {{ item.key }}"
  with_dict: "{{ options | default({ option | default(omit): value | default(None)}) }}"
  when: not (rootflags | default(False))

- name: Set kernel flags (append if present)
  replace:
    path: "{{ kernel_boot_cmdline }}"
    regexp: '{{ regex_preamble }}([''"])(.*?)(\2\s*)$'
    replace: '\1\2\3 {{ item.key }}={{ item.value | string }}\4'
  loop_control:
    label: "Adding {{ item.key }}={{ item.value }}"
  with_dict: "{{ options | default({ option | default(omit): value | default(None)}) }}"
  when:
    - not (rootflags | default(False))
    - state | default('present') == 'present'
  notify: Update grub

FWIW, this was the justification provided:

The key insight: one regex cannot reliably both consume and re-emit the closing quote when it’s also optional. Splitting strip and append into two tasks eliminates the problem entirely.

2

This was fixed in 9db57257. You’re on an older release.

Issue is interoperability between /etc/default/grub and /etc/kernel/cmdline syntax, which to support both quoted/non-quoted forms we have to optionally reject a backreference capture. Atomic grouping is ideal, but Python lacks true support for it and the alternative syntax is garish.

-    regexp: '{{ regex_preamble }}([''"])?((?:.(?!\s*{{ option | regex_escape }}=))*.)(?:\s*{{ option | regex_escape }}=\S+)?(.*)\2$'
+    regexp: '{{ regex_preamble }}([''"])?((?:.(?!\s*{{ item.key | regex_escape }}=))*.)(?:\s*{{ item.key | regex_escape }}=\S+)?(.*)\2?$'

Usage of ? to make a backreference non-greedy, which allowed .* - greedy by default - to race to the end of the match and discard its optional backreference (shell var quoting). Inserting a non-capturing boundary marker (\b) permits backreference usage in /etc/kernel/cmdline distros.

The Owl Book is a fantastic resource if you’d like to learn more about how regexes work.

3

Glad to know it’s fixed. I believe I tried it on Saturday and figured I’d submit a bug report today.
I didn’t check to see if a new commit resolved it, sorry.