The following sequence may cause the VM abort during migration:
1. RUN_STATE_RUNNING,MIGRATION_STATUS_ACTIVE
2. before call migration_completion(), we send migrate_cancel
QMP command, the state machine is changed to:
RUN_STATE_RUNNING,MIGRATION_STATUS_CANCELLING
3. call migration_completion(), and the state machine is
switch to: RUN_STATE_RUNNING,MIGRATION_STATUS_COMPLETED
4. call migration_iteration_finish(), because the migration
status is COMPLETED, so it will try to set the runstate
to POSTMIGRATE, but RUNNING-->POSTMIGRATE is an invalid
transition, so abort().
The migration_completion() should not change the migration state
to COMPLETED if it is already changed to CANCELLING.
Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Message-Id: <20201105091726.148-1-longpeng2@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>