Created attachment 1511269 [details]
logs

Description of problem:
Migration failed with libvirtError when certain migration policy and VM memory are set.

Version-Release number of selected component (if applicable):
Engine Version: 4.3.0-0.5.alpha1.el7
OS Version: RHEL - 7.6 - 4.el7
LIBVIRT Version: libvirt-4.5.0-10.el7_6.3
VDSM Version: vdsm-4.30.3-1.el7ev

How reproducible:
100%

Steps to Reproduce:
1. Set migration policy in cluster to minimal downtime and migration bandwidth to custom with 52 Mbps.
2. Find the host with the minimum free memory size in the environment
3. Create VM with memory size equals to 30% of the free memory of the host that you found at step 2.
4. Set the VM maximum memory to be equal to the VM memory size + 2GB.
4. Run VM.
5. Migrate VM. 

Actual results:
Migration completed fine.

Expected results:
Migration stuck and eventually failed with libvirtError.

Additional info:
2018-11-26 03:22:01,552+0200 ERROR (migsrc/1d1a5210) [virt.vm] (vmId='1d1a5210-2abe-43ad-bf47-5aef1565168e') Failed to migrate (migration:450)
Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/vdsm/virt/migration.py", line 431, in _regular_run
    time.time(), migrationParams, machineParams
  File "/usr/lib/python2.7/site-packages/vdsm/virt/migration.py", line 505, in _startUnderlyingMigration
    self._perform_with_conv_schedule(duri, muri)
  File "/usr/lib/python2.7/site-packages/vdsm/virt/migration.py", line 591, in _perform_with_conv_schedule
    self._perform_migration(duri, muri)
  File "/usr/lib/python2.7/site-packages/vdsm/virt/migration.py", line 525, in _perform_migration
    self._migration_flags)
  File "/usr/lib/python2.7/site-packages/vdsm/virt/virdomain.py", line 100, in f
    ret = attr(*args, **kwargs)
  File "/usr/lib/python2.7/site-packages/vdsm/common/libvirtconnection.py", line 131, in wrapper
    ret = f(*args, **kwargs)
  File "/usr/lib/python2.7/site-packages/vdsm/common/function.py", line 94, in wrapper
    return func(inst, *args, **kwargs)
  File "/usr/lib64/python2.7/site-packages/libvirt.py", line 1779, in migrateToURI3
    if ret == -1: raise libvirtError ('virDomainMigrateToURI3() failed', dom=self)
libvirtError: operation aborted: migration out job: canceled by client