Description of problem:

When exporting an OVA, the engine attempts to teardown the image even if the host used for export is running the VM. This fails as the VM is using the volumes. The engine does not handle the exception and the OVA export task "fails", when it actually just failed to teardown.

1. Export to OVA
2019-07-29 14:12:14,404+10 INFO  [org.ovirt.engine.core.bll.CreateOvaCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-5) [4ec10176] Running command: CreateOvaCommand internal: true.

2. Prepare (Why? The VM is running on the same host...)
2019-07-29 14:12:14,408+10 INFO  [org.ovirt.engine.core.vdsbroker.vdsbroker.PrepareImageVDSCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-5) [4ec10176] START, PrepareImageVDSCommand(HostName = rhel-h2, PrepareImageVDSCommandParameters:{hostId='ee5f0ee7-8c2c-4fc8-8b06-50e08242436b'}), log id: 6769ebe2

3. Export finishes

2019-07-29 14:12:43,075+10 INFO  [org.ovirt.engine.core.common.utils.ansible.AnsibleExecutor] (EE-ManagedThreadFactory-engineScheduled-Thread-5) [4ec10176] Ansible playbook command has exited with value: 0

4. Teardown (VM is running on the same host)
2019-07-29 14:12:43,086+10 INFO  [org.ovirt.engine.core.vdsbroker.vdsbroker.TeardownImageVDSCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-5) [4ec10176] START, TeardownImageVDSCommand(HostName = rhel-h2, ImageActionsVDSCommandParameters:{hostId='ee5f0ee7-8c2c-4fc8-8b06-50e08242436b'}), log id: 15033352

5. Teardown fails as the volume is in use

2019-07-29 14:13:03,061+10 ERROR [org.ovirt.engine.core.dal.dbbroker.auditloghandling.AuditLogDirector] (EE-ManagedThreadFactory-engineScheduled-Thread-5) [4ec10176] EVENT_ID: VDS_BROKER_COMMAND_FAILURE(10,802), VDSM rhel-h2 command TeardownImageVDS failed: Cannot deactivate Logical Volume: ('General Storage Exception: ("5 [] [\'  Logical volume e839d116-dc89-467e-a458-178706b6d581/7b68ad0a-e676-46c9-81ba-784f59e607f4 in use.\', \'  Logical volume e839d116-dc89-467e-a458-178706b6d581/e7a40ed3-b0a6-4eb6-9742-96262eb4989d in use.\']\\ne839d116-dc89-467e-a458-178706b6d581/[\'7b68ad0a-e676-46c9-81ba-784f59e607f4\', \'e7a40ed3-b0a6-4eb6-9742-96262eb4989d\']",)',)

6. OVA export Fails due to the exception from above

2019-07-29 14:13:03,072+10 ERROR [org.ovirt.engine.core.bll.SerialChildCommandsExecutionCallback] (EE-ManagedThreadFactory-engineScheduled-Thread-5) [4ec10176] EngineException: CannotDeactivateLogicalVolume (Failed with error CannotDeactivateLogicalVolume and code 552): org.ovirt.engine.core.common.errors.EngineException: EngineException: CannotDeactivateLogicalVolume (Failed with error CannotDeactivateLogicalVolume and code 552)
        at org.ovirt.engine.core.bll.exportimport.ExportOvaCommand.createOva(ExportOvaCommand.java:117) [bll.jar:]
        at org.ovirt.engine.core.bll.exportimport.ExportVmToOvaCommand.executeNextOperation(ExportVmToOvaCommand.java:224) [bll.jar:]
        at org.ovirt.engine.core.bll.exportimport.ExportVmToOvaCommand.performNextOperation(ExportVmToOvaCommand.java:216) [bll.jar:]
        at org.ovirt.engine.core.bll.SerialChildCommandsExecutionCallback.childCommandsExecutionEnded(SerialChildCommandsExecutionCallback.java:32) [bll.jar:]
        at org.ovirt.engine.core.bll.ChildCommandsCallbackBase.doPolling(ChildCommandsCallbackBase.java:77) [bll.jar:]
        at org.ovirt.engine.core.bll.tasks.CommandCallbacksPoller.invokeCallbackMethodsImpl(CommandCallbacksPoller.java:175) [bll.jar:]
        at org.ovirt.engine.core.bll.tasks.CommandCallbacksPoller.invokeCallbackMethods(CommandCallbacksPoller.java:109) [bll.jar:]
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [rt.jar:1.8.0_212]
        at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308) [rt.jar:1.8.0_212]
        at org.glassfish.enterprise.concurrent.internal.ManagedScheduledThreadPoolExecutor$ManagedScheduledFutureTask.access$201(ManagedScheduledThreadPoolExecutor.java:383) [javax.enterprise.concurrent.jar:1.0.0.redhat-1]
        at org.glassfish.enterprise.concurrent.internal.ManagedScheduledThreadPoolExecutor$ManagedScheduledFutureTask.run(ManagedScheduledThreadPoolExecutor.java:534) [javax.enterprise.concurrent.jar:1.0.0.redhat-1]
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [rt.jar:1.8.0_212]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [rt.jar:1.8.0_212]
        at java.lang.Thread.run(Thread.java:748) [rt.jar:1.8.0_212]
        at org.glassfish.enterprise.concurrent.ManagedThreadFactoryImpl$ManagedThread.run(ManagedThreadFactoryImpl.java:250) [javax.enterprise.concurrent.jar:1.0.0.redhat-1]

2019-07-29 14:13:03,075+10 INFO  [org.ovirt.engine.core.bll.SerialChildCommandsExecutionCallback] (EE-ManagedThreadFactory-engineScheduled-Thread-5) [4ec10176] Command 'ExportVmToOva' id: '53165a01-742d-494a-ba82-f883004d5f7f' child commands '[cdd0ff4b-38a1-4e1b-b7ab-3d47170efb20]' executions were completed, status 'FAILED'


7. Export "failed"

2019-07-29 14:13:05,153+10 ERROR [org.ovirt.engine.core.dal.dbbroker.auditloghandling.AuditLogDirector] (EE-ManagedThreadFactory-engineScheduled-Thread-71) [] EVENT_ID: IMPORTEXPORT_EXPORT_VM_TO_OVA_FAILED(1,225), Failed to export Vm ASD as a Virtual Appliance to path /tmp/ASD.ova on Host rhel-h2

Version-Release number of selected component (if applicable):
rhvm-4.3.4.3-0.1.el7.noarch
vdsm-4.30.17-1.el7ev.x86_64

How reproducible:
Always

Steps to Reproduce:
1. Create VM with disk on block storage
2. Start VM
3. Export as OVA using the same host running the VM

Actual results:
OVA is created, but engine fails due to exception on teardown

Expected results:
Do not teardown if the host is running the VM, or handle the exception