Add option for extra kernel modules in neutron role

Closes-Bug: #2036741

Change-Id: Ib448d04e43dff78e344064161beadae917c41206

ansible/roles/neutron/defaults/main.yml

@@ -712,6 +712,13 @@ neutron_bootstrap_services: "{{ neutron_subprojects | selectattr('enabled') | ma
 neutron_enable_rolling_upgrade: "yes"
 neutron_rolling_upgrade_services: "{{ neutron_subprojects | selectattr('enabled') | map(attribute='name') | list }}"
 
+####################
+# Neutron modules
+####################
+neutron_modules_default:
+  - name: 'ip6_tables'
+neutron_modules_extra: []
+
 ####################
 # Service Plugins
 ####################

ansible/roles/neutron/tasks/config-host.yml

@@ -1,10 +1,9 @@
 ---
-- name: Load and persist ip6_tables module
+- name: Load and persist kernel modules
   include_role:
     name: module-load
   vars:
-    modules:
+    modules: "{{ neutron_modules_default + neutron_modules_extra }}"
-      - {'name': ip6_tables}
   when: >-
     neutron_services |
     select_services_enabled_and_mapped_to_host |

doc/source/reference/networking/neutron.rst

@@ -214,3 +214,25 @@ authentication in external systems (e.g. in ``networking-generic-switch`` or
 
 You can set ``neutron_ssh_key`` variable in ``passwords.yml`` to control the
 used key.
+
+Custom Kernel Module Configuration for Neutron
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Neutron may require specific kernel modules for certain functionalities.
+While there are predefined default modules in the Ansible role, users have
+the flexibility to add custom modules as needed.
+
+To add custom kernel modules for Neutron, modify the configuration in
+``/etc/kolla/globals.yml``:
+
+.. code-block:: yaml
+
+   neutron_modules_extra:
+     - name: 'nf_conntrack_tftp'
+       params: 'hashsize=4096'
+
+In this example:
+
+- `neutron_modules_extra`: Allows users to specify additional modules and
+  their associated parameters. The given configuration adjusts the
+  `hashsize` parameter for the `nf_conntrack_tftp` module.

releasenotes/notes/add-neutron-custom-kernel-modules-d105d3f84665e0a4.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    Added capability to specify custom kernel modules for Neutron:
+    `neutron_modules_default`: Lists default modules.
+    `neutron_modules_extra`: For custom modules and parameters.

tests/templates/globals-default.j2

@@ -198,3 +198,7 @@ enable_venus: "yes"
 {% if groups['all'] | length == 1 %}
 keepalived_track_script_enabled: "no"
 {% endif %}
+
+neutron_modules_extra:
+  - name: 'nf_conntrack_tftp'
+  - name: 'nf_nat_tftp'

tests/test-core-openstack.sh

@@ -209,6 +209,25 @@ function unset_cirros_image_q35_machine_type {
     openstack image unset --property hw_machine_type cirros
 }
 
+function test_neutron_modules {
+    # Exit the function if scenario is "ovn" or if there's an upgrade
+    # as inly concerns ml2/ovs
+    if [[ $SCENARIO == "ovn" ]] || [[ $HAS_UPGRADE == "yes" ]]; then
+        return
+    fi
+
+    local modules
+    modules=( $(sed -n '/neutron_modules_extra:/,/^[^ ]/p' /etc/kolla/globals.yml | grep -oP '^  - name: \K[^ ]+' | tr -d "'") )
+    for module in "${modules[@]}"; do
+        if ! grep -q "^${module} " /proc/modules; then
+            echo "Error: Module $module is not loaded."
+            exit 1
+        else
+            echo "Module $module is loaded."
+        fi
+    done
+}
+
 function test_ssh {
     local instance_name=$1
     local fip_addr=$2
@@ -354,6 +373,7 @@ function test_openstack_logged {
     . /etc/kolla/admin-openrc.sh
     . ~/openstackclient-venv/bin/activate
     test_smoke
+    test_neutron_modules
     test_instance_boot
 
     # Check for x86_64 architecture to run q35 tests