Add `instance_info/kernel_append_params` to `redfish`

Adds `instance_info/kernel_append_params` property support to
`redfish` hardware type. If given, this property overrides
`[redfish]/kernel_append_params` ironic option.

The rationale for adding this property is to allow passing
node-specific kernel parameters to instance kernel.

One of the use-cases for this is to pass node static network
configuration to the kernel.

Change-Id: Ib1617f5a7ab34968d8bfe06fe49f3ba68e56f99f
Story: 2006691
Task: 36988

doc/source/admin/drivers/redfish.rst

@@ -176,6 +176,12 @@ If ``[driver_info]/config_via_floppy`` boolean property of the node is set to
 place into on a FAT image, then insert the image into node's virtual floppy
 drive.
 
+When booting over PXE or virtual media, and user instance requires some
+specific kernel configuration, ``[instance_info]/kernel_append_params``
+property can be used to pass user-specified kernel command line parameters.
+For ramdisk kernel, ``[instance_info]/kernel_append_params`` property serves
+the same purpose.
+
 .. _Redfish: http://redfish.dmtf.org/
 .. _Sushy: https://opendev.org/openstack/sushy
 .. _TLS: https://en.wikipedia.org/wiki/Transport_Layer_Security

ironic/conf/redfish.py

@@ -62,8 +62,12 @@ opts = [
                       'enabled.')),
     cfg.StrOpt('kernel_append_params',
                default='nofb nomodeset vga=normal',
-               help=_('Additional kernel parameters for baremetal '
-                      'Virtual Media boot.')),
+               help=_('Additional kernel parameters to pass down to the '
+                      'instance kernel. These parameters can be consumed by '
+                      'the kernel or by the applications by reading '
+                      '/proc/cmdline. Mind severe cmdline size limit! Can be '
+                      'overridden by `instance_info/kernel_append_params` '
+                      'property.')),
 ]
 
 

ironic/drivers/modules/redfish/boot.py

@@ -50,11 +50,19 @@ OPTIONAL_PROPERTIES = {
                            "driver should use virtual media Floppy device "
                            "for passing configuration information to the "
                            "ramdisk. Defaults to False. Optional."),
+    'kernel_append_params': _("Additional kernel parameters to pass down to "
+                              "instance kernel. These parameters can be "
+                              "consumed by the kernel or by the applications "
+                              "by reading /proc/cmdline. Mind severe cmdline "
+                              "size limit. Overrides "
+                              "[redfish]/kernel_append_params ironic "
+                              "option."),
     'bootloader': _("URL or Glance UUID  of the EFI system partition "
                     "image containing EFI boot loader. This image will be "
                     "used by ironic when building UEFI-bootable ISO "
                     "out of kernel and ramdisk. Required for UEFI "
-                    "boot from partition images.")
+                    "boot from partition images."),
+
 }
 
 RESCUE_PROPERTIES = {
@@ -431,12 +439,15 @@ class RedfishVirtualMediaBoot(base.BootInterface):
                 "building ISO for %(node)s") %
                 {'node': task.node.uuid})
 
+        i_info = task.node.instance_info
+
         if deploy_utils.get_boot_option(task.node) == "ramdisk":
-            i_info = task.node.instance_info
             kernel_params = "root=/dev/ram0 text "
             kernel_params += i_info.get("ramdisk_kernel_arguments", "")
+
         else:
-            kernel_params = CONF.redfish.kernel_append_params
+            kernel_params = i_info.get(
+                'kernel_append_params', CONF.redfish.kernel_append_params)
 
         if params:
             kernel_params = ' '.join(

ironic/tests/unit/drivers/modules/redfish/test_boot.py

@@ -397,6 +397,27 @@ class RedfishVirtualMediaBootTestCase(db_base.DbTestCase):
 
             self.assertEqual(expected_url, url)
 
+    @mock.patch.object(redfish_boot.RedfishVirtualMediaBoot,
+                       '_publish_image', autospec=True)
+    @mock.patch.object(images, 'create_boot_iso', autospec=True)
+    def test__prepare_iso_image_kernel_params(
+            self, mock_create_boot_iso, mock__publish_image):
+        with task_manager.acquire(self.context, self.node.uuid,
+                                  shared=True) as task:
+            kernel_params = 'network-config=base64-cloudinit-blob'
+
+            task.node.instance_info.update(kernel_append_params=kernel_params)
+
+            task.driver.boot._prepare_iso_image(
+                task, 'http://kernel/img', 'http://ramdisk/img',
+                bootloader_href=None, root_uuid=task.node.uuid)
+
+            mock_create_boot_iso.assert_called_once_with(
+                mock.ANY, mock.ANY, 'http://kernel/img', 'http://ramdisk/img',
+                boot_mode=None, esp_image_href=None,
+                kernel_params=kernel_params,
+                root_uuid='1be26c0b-03f2-4d2e-ae87-c02d7f33c123')
+
     @mock.patch.object(redfish_boot.RedfishVirtualMediaBoot,
                        '_prepare_iso_image', autospec=True)
     def test__prepare_deploy_iso(self, mock__prepare_iso_image):

releasenotes/notes/add-kernel-params-redfish-72b87075465c87f6.yaml

@@ -0,0 +1,9 @@
+---
+features:
+  - |
+    Adds ``instance_info/kernel_append_params`` property support to ``redfish``
+    hardware type. If given, this property overrides
+    ``[redfish]/kernel_append_params`` ironic option. The rationale for adding
+    this property is to allow passing node-specific kernel parameters to instance
+    kernel. One of the use-cases for this is to pass node static network
+    configuration to the kernel.