Created attachment 1504928 [details]
logs and screenshot

Description of problem:
A failure to live merge the auto generated snapshot that was created during live storage migration.


Version-Release number of selected component (if applicable):
rhvm-4.2.7.4-0.1.el7ev.noarch
vdsm-4.20.43-1.el7ev.x86_64
libvirt-4.5.0-10.el7_6.2.x86_64
qemu-kvm-rhev-2.12.0-18.el7_6.1.x86_64
kernel 3.10.0-957.el7.x86_64 


How reproducible:
Happened after the below scenario, havn't tried it again

Steps to Reproduce:
Happened after the following scenario:

- Created a VM created with a disk on iSCSI (SD1)
- Started the VM
- Live migrated the VM disk to another iSCSI domain (SD2) 
- Attached a direct LUN with virtio-scsi enabled 
- Live migrated the VM disk to another iSCSI domain (SD3)


Actual results:
Failed to delete snapshot 'disk_create_and_attach_disk_1223324525 Auto-generated for Live Storage Migration' for VM 'vm_create_vm_1223264526':


2018-11-12 23:38:59,575+02 ERROR [org.ovirt.engine.core.bll.MergeStatusCommand] (EE-ManagedThreadFactory-commandCoordinator-Thread-8) [disks_syncAction_f7107428-c02c-4b5d] Command 'org.ovirt.engine.core.bll.MergeStatusCommand' failed: Invalid UUID string: mapper
2018-11-12 23:38:59,576+02 ERROR [org.ovirt.engine.core.bll.MergeStatusCommand] (EE-ManagedThreadFactory-commandCoordinator-Thread-8) [disks_syncAction_f7107428-c02c-4b5d] Exception: java.lang.IllegalArgumentException: Invalid UUID string: mapper
        at java.util.UUID.fromString(UUID.java:194) [rt.jar:1.8.0_181]
        at org.ovirt.engine.core.compat.Guid.<init>(Guid.java:67) [compat.jar:]
        at org.ovirt.engine.core.compat.Guid.createGuidFromStringWithDefault(Guid.java:87) [compat.jar:]
        at org.ovirt.engine.core.compat.Guid.createGuidFromString(Guid.java:76) [compat.jar:]
        at org.ovirt.engine.core.bll.MergeStatusCommand.getVolumeChain(MergeStatusCommand.java:152) [bll.jar:]
        at org.ovirt.engine.core.bll.MergeStatusCommand.attemptResolution(MergeStatusCommand.java:75) [bll.jar:]
        at org.ovirt.engine.core.bll.MergeStatusCommand.executeCommand(MergeStatusCommand.java:59) [bll.jar:]
        at org.ovirt.engine.core.bll.CommandBase.executeWithoutTransaction(CommandBase.java:1146) [bll.jar:]
        at org.ovirt.engine.core.bll.CommandBase.executeActionInTransactionScope(CommandBase.java:1303) [bll.jar:]
        at org.ovirt.engine.core.bll.CommandBase.runInTransaction(CommandBase.java:1952) [bll.jar:]




Expected results:
Live merge should succeed. Not sure if related, but later operations on that disk and VM, like VM migration will fail too (in logs, host2, the destination host for VM migration. The source host was host1):


2018-11-12 23:47:49,389+0200 ERROR (vm/faaab84f) [virt.vm] (vmId='faaab84f-85be-49f4-afae-34a95f49ecb3') The vm start process failed (vm:948)
Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/vdsm/virt/vm.py", line 877, in _startUnderlyingVm
    self._run()
  File "/usr/lib/python2.7/site-packages/vdsm/virt/vm.py", line 2802, in _run
    self._devices = self._make_devices()
  File "/usr/lib/python2.7/site-packages/vdsm/virt/vm.py", line 2643, in _make_devices
    disk_objs = self._perform_host_local_adjustment()
  File "/usr/lib/python2.7/site-packages/vdsm/virt/vm.py", line 2716, in _perform_host_local_adjustment
    self._preparePathsForDrives(disk_params)
  File "/usr/lib/python2.7/site-packages/vdsm/virt/vm.py", line 1022, in _preparePathsForDrives
    drive['path'] = self.cif.prepareVolumePath(drive, self.id)
  File "/usr/lib/python2.7/site-packages/vdsm/clientIF.py", line 417, in prepareVolumePath
    raise vm.VolumeError(drive)
VolumeError: Bad volume specification {'address': {'slot': '0x09', 'bus': '0x00', 'domain': '0x0000', 'type': 'pci', 'function': '0x0'}, 'serial': 'be0ff91b-a137-4f4d-87b3-1ec5825b29a0', 'index': 0, 'iface': 'vi
rtio', 'apparentsize': '1207959552', 'specParams': {'pinToIoThread': '1'}, 'cache': 'none', 'imageID': 'be0ff91b-a137-4f4d-87b3-1ec5825b29a0', 'truesize': '1207959552', 'type': 'disk', 'domainID': '5901a2ff-e298
-43ea-b183-828c9645eb28', 'reqsize': '0', 'format': 'cow', 'poolID': '33153d4d-f83e-4163-9112-ca7b2333aaa2', 'device': 'disk', 'path': '/rhev/data-center/mnt/blockSD/5901a2ff-e298-43ea-b183-828c9645eb28/images/b
e0ff91b-a137-4f4d-87b3-1ec5825b29a0/23b99597-7edf-4950-891a-5d2b3eb89184', 'propagateErrors': 'off', 'name': 'vda', 'volumeID': '23b99597-7edf-4950-891a-5d2b3eb89184', 'diskType': 'block', 'alias': 'ua-be0ff91b-
a137-4f4d-87b3-1ec5825b29a0', 'discard': False, 'volumeChain': [{'domainID': '5901a2ff-e298-43ea-b183-828c9645eb28', 'leaseOffset': 112197632, 'volumeID': '23b99597-7edf-4950-891a-5d2b3eb89184', 'leasePath': '/d
ev/5901a2ff-e298-43ea-b183-828c9645eb28/leases', 'imageID': 'be0ff91b-a137-4f4d-87b3-1ec5825b29a0', 'path': '/rhev/data-center/mnt/blockSD/5901a2ff-e298-43ea-b183-828c9645eb28/images/be0ff91b-a137-4f4d-87b3-1ec5
825b29a0/23b99597-7edf-4950-891a-5d2b3eb89184'}]}


Additional info:
Logs and screenshot from webadmin with all the operations done for the relevant VM.