Software RAID: Don't delete partitions too early

Partions on the holder disk should only be deleted after
all RAID devices have been deleted. Otherwise, super blocks
on partitions which reside on the same disks cannot be cleaned.

Story: #2008199
Task: #40979
Change-Id: I19293f5b992cd1fa68957d6f306dcec8f3b7a820

ironic_python_agent/hardware.py

@@ -1881,6 +1881,7 @@ class GenericHardwareManager(HardwareManager):
             raise errors.SoftwareRAIDError(msg)
 
     def _delete_config_pass(self, raid_devices):
+        all_holder_disks = []
         for raid_device in raid_devices:
             component_devices = _get_component_devices(raid_device.name)
             if not component_devices:
@@ -1933,14 +1934,11 @@ class GenericHardwareManager(HardwareManager):
                     LOG.warning('Failed to remove superblock from %s: %s',
                                 raid_device.name, e)
 
-            # Remove the partitions we created during create_configuration.
+            # NOTE(arne_wiebalck): We cannot delete the partitions right
-            for holder_disk in holder_disks:
+            # away since there may be other partitions on the same disks
-                LOG.debug('Removing partitions on %s', holder_disk)
+            # which are members of other RAID devices. So we remember them
-                try:
+            # for later.
-                    utils.execute('wipefs', '-af', holder_disk)
+            all_holder_disks.extend(holder_disks)
-                except processutils.ProcessExecutionError:
-                    LOG.warning('Failed to remove partitions on %s',
-                                holder_disk)
 
             LOG.info('Deleted Software RAID device %s', raid_device.name)
 
@@ -1986,6 +1984,17 @@ class GenericHardwareManager(HardwareManager):
                 LOG.warning('Failed to remove superblock from %s: %s',
                             raid_device.name, e)
 
+        # Erase all partition tables we created
+        all_holder_disks_uniq = list(
+            collections.OrderedDict.fromkeys(all_holder_disks))
+        for holder_disk in all_holder_disks_uniq:
+            LOG.info('Removing partitions on holder disk %s', holder_disk)
+            try:
+                utils.execute('wipefs', '-af', holder_disk)
+            except processutils.ProcessExecutionError as e:
+                LOG.warning('Failed to remove partitions on %s',
+                            holder_disk, e)
+
         LOG.debug("Finished deleting Software RAID(s)")
 
     def validate_configuration(self, raid_config, node):

ironic_python_agent/tests/unit/test_hardware.py

@@ -4016,8 +4016,6 @@ class TestGenericHardwareManager(base.IronicAgentTest):
             mock.call('mdadm', '--examine', '/dev/sdb1',
                       use_standard_locale=True),
             mock.call('mdadm', '--zero-superblock', '/dev/sdb1'),
-            mock.call('wipefs', '-af', '/dev/sda'),
-            mock.call('wipefs', '-af', '/dev/sdb'),
             mock.call('wipefs', '-af', '/dev/md1'),
             mock.call('mdadm', '--stop', '/dev/md1'),
             mock.call('mdadm', '--examine', '/dev/sda2',
@@ -4026,15 +4024,17 @@ class TestGenericHardwareManager(base.IronicAgentTest):
             mock.call('mdadm', '--examine', '/dev/sdb2',
                       use_standard_locale=True),
             mock.call('mdadm', '--zero-superblock', '/dev/sdb2'),
-            mock.call('wipefs', '-af', '/dev/sda'),
-            mock.call('wipefs', '-af', '/dev/sdb'),
             mock.call('mdadm', '--examine', '/dev/sdc',
                       use_standard_locale=True),
             mock.call('mdadm', '--zero-superblock', '/dev/sdc'),
             mock.call('mdadm', '--examine', '/dev/sdb',
                       use_standard_locale=True),
+            mock.call('mdadm', '--zero-superblock', '/dev/sdb'),
             mock.call('mdadm', '--examine', '/dev/sda',
                       use_standard_locale=True),
+            mock.call('mdadm', '--zero-superblock', '/dev/sda'),
+            mock.call('wipefs', '-af', '/dev/sda'),
+            mock.call('wipefs', '-af', '/dev/sdb'),
             mock.call('mdadm', '--assemble', '--scan', check_exit_code=False),
         ])
 

releasenotes/notes/fix_partition_cleanup-46491861c930db12.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    Fixes a bug where the partitions created during software RAID setup are cleaned
+    too early and therefore may prevent the proper cleaning of the md superblocks.
+    Leaving superblocks behind will impact the creation of new md devices later on.