Pin nvidia driver version

ansible/roles/cuda/README.md

@@ -10,6 +10,7 @@ Requires OFED to be installed to provide required kernel-* packages.
 
 - `cuda_repo_url`: Optional. URL of `.repo` file. Default is upstream for appropriate OS/architecture.
 - `cuda_nvidia_driver_stream`: Optional. Version of `nvidia-driver` stream to enable. This controls whether the open or proprietary drivers are installed and the major version. Changing this once the drivers are installed does not change the version.
+- `cuda_nvidia_driver_version`: Optional. Version of `nvidia-driver` module to install.
 - `cuda_packages`: Optional. Default: `['cuda', 'nvidia-gds', 'cmake', 'cuda-toolkit-12-8']`.
 - `cuda_package_version`: Optional. Default `latest` which will install the latest packages if not installed but won't upgrade already-installed packages. Use `'none'` to skip installing CUDA.
 - `cuda_persistenced_state`: Optional. State of systemd `nvidia-persistenced` service. Values as [ansible.builtin.systemd:state](https://docs.ansible.com/ansible/latest/collections/ansible/builtin/systemd_module.html#parameter-state). Default `started`.

ansible/roles/cuda/defaults/main.yml

@@ -1,5 +1,6 @@
 cuda_repo_url: "https://developer.download.nvidia.com/compute/cuda/repos/rhel{{ ansible_distribution_major_version }}/{{ ansible_architecture }}/cuda-rhel{{ ansible_distribution_major_version }}.repo"
 cuda_nvidia_driver_stream: '570-open'
+cuda_nvidia_driver_version: '570.133.20-1.el9' # version-release format
 cuda_package_version: '12.8.1-1'
 cuda_version_short: '12.8'
 cuda_packages:

ansible/roles/cuda/library/dnf_module_info.py

@@ -0,0 +1,79 @@
+from ansible.module_utils.basic import AnsibleModule
+import subprocess
+
+DOCUMENTATION = r'''
+module: dnf_module_info
+description: Return a list of packages which would be installed by a dnf module
+options:
+    name:
+        description: The dnf module name
+        required: true
+        type: str
+    stream:
+        description: The stream to query
+        required: true
+        type: str
+'''
+
+RETURN = r'''
+info:
+    description: The version/context etc for the module
+    type: list
+    returned: always
+profiles:
+    description: A mapping, keyed by profile name, where values are a list
+                 of packages this profile will install
+    type: dict
+    returned: always
+stdout:
+    description: Raw stdout from the dnf command
+    type: str
+    returned: always
+'''
+
+def dnf_module_packages():
+    module_args = dict(
+        name=dict(type='str', required=True),
+        stream=dict(type='str', required=True)
+    )
+    result = {'changed': False}
+
+    module = AnsibleModule(
+        argument_spec=module_args,
+        supports_check_mode=True
+    )
+    dnf_module_name = module.params['name']
+    dnf_module_stream = module.params['stream']
+
+    # first get the list of packages installed by the module
+    cmd = ['dnf', 'module', 'info', '--profile',  f'{dnf_module_name}:{dnf_module_stream}']
+    dnf = subprocess.run(cmd,  capture_output=True, text=True)
+
+    curr_profile_name = ''
+    profiles = {}
+    for line in dnf.stdout.splitlines():
+        if line.startswith('Last'): # metadata expiration info
+            continue
+        elif not ':' in line:
+            continue
+        elif line.startswith('Name'):
+            info = [v.strip() for v in line.split(':')]
+        else:
+            try:
+                profile, pkg = (v.strip() for v in line.split(':'))
+            except ValueError:
+                raise ValueError(line)
+            if profile != '' and profile != curr_profile_name:
+                curr_profile_name = profile
+                profiles[profile] = []
+            profiles[curr_profile_name].append(pkg)
+
+
+    result['info'] = info
+    result['profiles'] = profiles
+    result['stdout'] = dnf.stdout
+    module.exit_json(**result)
+
+
+if __name__ == '__main__':
+    dnf_module_packages()

ansible/roles/cuda/tasks/install.yml

@@ -29,17 +29,26 @@
   when: "'No matching Modules to list' in _cuda_driver_module_enabled.stderr"
   changed_when: "'Nothing to do' not in _cuda_driver_module_enable.stdout"
 
-- name: Check if nvidia driver module is installed
-  ansible.builtin.command: dnf module list --installed nvidia-driver
-  changed_when: false
-  failed_when: false
-  register: _cuda_driver_module_installed
+- name: Read module info for list of packages
+  # Even a single version of the module stream contains multiple package versions
+  # so need to find the ones we want.
+  dnf_module_info:
+    name: nvidia-driver
+    stream: "{{ cuda_nvidia_driver_stream }}"
+  register: _cuda_driver_module_info
 
-- name: Install nvidia drivers
-  ansible.builtin.command: dnf module install -y nvidia-driver
+- name: Install nvidia driver packages for specific version
+  # entries in package list from above are e.g. 'nvidia-driver', where the
+  # actual package name is 'nvidia-driver-3:570.133.20-1.el9.x86_64'
+  # The epoch (3) and arch (x86_64) can be omitted but the release (1.el9)
+  # cannot be, so need to generate e.g. 'nvidia-driver-570.133.20-1.el9'
+  ansible.builtin.dnf:
+    name: >-
+      {{
+        _cuda_driver_module_info.profiles.default |
+        map('regex_replace', '$', '-' ~ cuda_nvidia_driver_version)
+      }}
   register: _cuda_driver_install
-  when: "'No matching Modules to list' in _cuda_driver_module_installed.stderr"
-  changed_when: "'Nothing to do' not in _cuda_driver_install.stdout"
 
 - name: Check kernel has not been modified
   assert: