Keep current kernel version if matching.

README.md

@@ -3,7 +3,7 @@
 Linux Kernel Role
 =================
 
-This Ansible role install and enable a specific kernel version from OS repositories.
+This Ansible role install and enable a specific kernel version from OS repositories and to ensure matching kernel headers are installed.
 
 Requirements
 ------------
@@ -15,9 +15,12 @@ The specified Kernel version must be supported by OS repositories (This include
 Role Variables
 --------------
 
-* **install_kernel_headers**: If True, also install matching kernel headers. Default to `true`.
-* **kernel_version**: Install the most recent kernel version available that start by this value. Default to `''`.
-* **reboot_on_kernel_update**: If True, reboot the system if the kernel was updated. Default to `true`.
+* **install_kernel_headers**: If True, also install matching kernel headers.
+  Default to `true`.
+* **kernel_version**: Install the most recent kernel version available that start by this value (Keep the current kernel version if matching).
+  Default to any version.
+* **reboot_on_kernel_update**: If True, reboot the system if the kernel was updated.
+  Default to `true`.
 
 Example Playbook
 ----------------

defaults/main.yml

@@ -2,7 +2,7 @@
 # Install kernel headers
 install_kernel_headers: true
 
-# Kernel version to install (Default to latest available)
+# Kernel version to install (Default to any version)
 kernel_version: ''
 
 # Reboot if kernel was updated

filter_plugins/main.py

@@ -1,19 +1,24 @@
 """Extra Ansible filters"""
 
 
-def _rhel_kernel_info(packages, kernel_version):
+def _rhel_kernel_info(packages, kernel_version, current_version):
     """
     Return kernel to install with associated repository.
 
     Args:
         packages (dict): DNF/YUM list output.
         kernel_version (str): Kernel version to install.
+        current_version (str): Current kernel version.
 
     Returns:
        dict: kernel version, repository
     """
     kernels = list()
 
+    # If current version match with required version, use this version
+    if current_version.startswith(kernel_version):
+        kernel_version = current_version
+
     # List all available kernel version and associated repository
     for line in packages['stdout'].splitlines():
         if line.startswith('kernel.') and not line.startswith('kernel.src'):
@@ -31,47 +36,56 @@ def _rhel_kernel_info(packages, kernel_version):
             ', '.join(kernel['version'] for kernel in kernels)))
 
 
-def rhel_kernel(packages, kernel_version):
+def rhel_kernel(packages, kernel_version, current_version):
     """
     Return matching kernel version to install.
 
     Args:
         packages (dict): DNF/YUM list output.
         kernel_version (str): Kernel version to install.
+        current_version (str): Current kernel version.
 
     Returns:
        str: kernel version.
     """
-    return _rhel_kernel_info(packages, kernel_version)['version']
+    return _rhel_kernel_info(
+        packages, kernel_version, current_version)['version']
 
 
-def rhel_repo(packages, kernel_version):
+def rhel_repo(packages, kernel_version, current_version):
     """
     Return repository where found specified kernel version.
 
     Args:
         packages (dict): DNF/YUM list output.
         kernel_version (str): Kernel version to install.
+        current_version (str): Current kernel version.
 
     Returns:
        str: repository name
     """
-    return _rhel_kernel_info(packages, kernel_version)['repo']
+    return _rhel_kernel_info(
+        packages, kernel_version, current_version)['repo']
 
 
-def deb_kernel(packages, kernel_version):
+def deb_kernel(packages, kernel_version, current_version):
     """
     Return best matching kernel version.
 
     Args:
         packages (dict): apt-cache showpkg output.
         kernel_version (str): Kernel version to install.
+        current_version (str): Current kernel version.
 
     Returns:
        str: kernel version.
     """
     kernels = set()
 
+    # If current version match with required version, use this version
+    if current_version.startswith(kernel_version):
+        kernel_version = current_version
+
     # List all available kernel version and associated repository
     for line in packages['stdout'].splitlines():
         line = line.strip()
@@ -133,13 +147,14 @@ def _deb_kernel_package(kernel, dist, arch, name):
     return '-'.join((name, kernel, suffix))
 
 
-def deb_kernel_pkg(packages, kernel_version, dist, arch, name):
+def deb_kernel_pkg(packages, kernel_version, current_version, dist, arch, name):
     """
     Return kernel package to install.
 
     Args:
         packages (dict): apt-cache showpkg output.
         kernel_version (str): Kernel version to install.
+        current_version (str): Current kernel version.
         dist (str): Distribution.
         arch (str): Architecture.
         name (str): Package name.
@@ -148,23 +163,24 @@ def deb_kernel_pkg(packages, kernel_version, dist, arch, name):
        str: kernel package to install.
     """
     return _deb_kernel_package(
-        deb_kernel(packages, kernel_version), dist, arch, name)
+        deb_kernel(packages, kernel_version, current_version), dist, arch, name)
 
 
-def deb_installed_kernel(installed, packages, kernel_version):
+def deb_installed_kernel(installed, packages, kernel_version, current_version):
     """
     Return old kernel packages to remove.
 
     Args:
         installed (dict): dpkg -l output.
         packages (dict): apt-cache showpkg output.
         kernel_version (str): Kernel version to install.
+        current_version (str): Current kernel version.
 
     Returns:
        list of str: Kernel packages to remove.
     """
     # Filter installed package to keep
-    to_keep = deb_kernel(packages, kernel_version)
+    to_keep = deb_kernel(packages, kernel_version, current_version)
 
     # Return installed package to remove
     to_remove = []

meta/main.yml

@@ -14,8 +14,8 @@ galaxy_info:
         - 8
     - name: Fedora
       versions:
-        - 29
         - 30
+        - 31
     - name: Ubuntu
       versions:
         - xenial

molecule/default/molecule.yml

@@ -11,8 +11,6 @@ platforms:
     image: centos:7
   - name: centos_8
     image: centos:8
-  - name: fedora_30
-    image: fedora:30
   - name: debian_buster
     image: debian:buster
   - name: ubuntu_bionic
@@ -23,10 +21,15 @@ provisioner:
     name: ansible-lint
   inventory:
     host_vars:
+      # Warning: Always specify a version: bad version detected from container
       centos_7:
         kernel_version: 3.10.0-693
+      centos_8:
+        kernel_version: 4.18.0
       ubuntu_bionic:
         kernel_version: 4.15.0
+      debian_buster:
+        kernel_version: 4.19.0
 verifier:
   name: testinfra
   lint:

tasks/main.yml

@@ -19,13 +19,15 @@
   register: yum_kernel_list
 
 - name: Set target YUM kernel version
-  set_fact: _kernel="{{ yum_kernel_list | rhel_kernel(kernel_version) }}"
+  set_fact: _kernel="{{ yum_kernel_list |
+                     rhel_kernel(kernel_version, ansible_kernel) }}"
   when: yum_kernel_list is not skipped
 
 - name: Ensure kernel packages versions with YUM
   yum:
     name: "{{ item.name }}-{{ _kernel }}"
-    enablerepo: "{{ yum_kernel_list | rhel_repo(kernel_version) }}"
+    enablerepo: "{{ yum_kernel_list |
+                 rhel_repo(kernel_version, ansible_kernel) }}"
     allow_downgrade: true
   when:
     - ansible_os_family == 'RedHat'
@@ -50,13 +52,15 @@
   register: dnf_kernel_list
 
 - name: Set target DNF kernel version
-  set_fact: _kernel="{{ dnf_kernel_list | rhel_kernel(kernel_version) }}"
+  set_fact: _kernel="{{ dnf_kernel_list |
+                     rhel_kernel(kernel_version, ansible_kernel) }}"
   when: dnf_kernel_list is not skipped
 
 - name: Ensure kernel packages versions with DNF
   dnf:
     name: "{{ item.name }}-{{ _kernel }}"
-    enablerepo: "{{ dnf_kernel_list | rhel_repo(kernel_version) }}"
+    enablerepo: "{{ dnf_kernel_list |
+                 rhel_repo(kernel_version, ansible_kernel) }}"
     allow_downgrade: true
   when:
     - ansible_os_family == 'RedHat'
@@ -91,14 +95,15 @@
   register: apt_packages_list
 
 - name: Set target APT kernel version
-  set_fact: _kernel="{{ apt_kernel_list | deb_kernel(kernel_version) }}"
+  set_fact: _kernel="{{ apt_kernel_list |
+                     deb_kernel(kernel_version, ansible_kernel) }}"
   when: apt_kernel_list is not skipped
 
 - name: Ensure kernel packages versions with APT
   apt:
     name: "{{ apt_kernel_list | deb_kernel_pkg(
-           kernel_version, ansible_distribution, ansible_architecture,
-           item.name) }}"
+           kernel_version, ansible_kernel, ansible_distribution,
+           ansible_architecture, item.name) }}"
   when:
     - ansible_os_family == 'Debian'
     - item.when
@@ -111,7 +116,7 @@
 - name: Ensure any other kernel packages are removed with APT
   apt:
     name: "{{ apt_packages_list | deb_installed_kernel(
-           apt_kernel_list, kernel_version) }}"
+           apt_kernel_list, kernel_version, ansible_kernel) }}"
     state: absent
     purge: true
   when: ansible_os_family == 'Debian'