A specific instance can not be live migrated on OSP 7

Issue

• Attempting to perform a live migration of a specific instance to another compute node causes the following error.

  [stack@undercloud00 ~(overcloud_admin)]$ nova live-migration  13150b91-045a-433f-811d-a9beff815580 compute03.localdomain --block-migrate --disk-over-commit
  
  [root@compute02 ~]# grep Migration /var/log/nova/nova-compute.log
  2016-11-21 15:45:37.201 10644 TRACE nova.compute.manager [instance: 792f0662-b09c-4208-97e7-a5367fd5e276] MigrationError_Remote: Migration error: Cannot block migrate instance 792f0662-b09c-4208-97e7-a5367fd5e276 with mapped volumes
  2016-11-21 15:45:37.201 10644 TRACE nova.compute.manager [instance: 792f0662-b09c-4208-97e7-a5367fd5e276]     raise exception.MigrationError(reason=msg)
  2016-11-21 15:45:37.201 10644 TRACE nova.compute.manager [instance: 792f0662-b09c-4208-97e7-a5367fd5e276] MigrationError: Migration error: Cannot block migrate instance 792f0662-b09c-4208-97e7-a5367fd5e276 with mapped volumes
  

• Observed only on certain instances.
     (When I tried several instances, this seems to occur only on an instance with volumes created from SnapShot)

• There are some instances which successfully finished live migration with the same command.
     (Those are newly created instance)