just marked https://bugs.launchpad.net/tripleo/+bug/1790932 as duplicate of this, but I'm copy/pasting the description as it includes a trace which is missing here thanks

(COPY/PASTE from +bug/1790932 ):

skipping: [127.0.0.2] [0/1928]│·
                                                                                                                                                                                                                   │·
TASK [fetch-images : Clean image cache directory] *****************************************************************************************************************************************************************│·
changed: [127.0.0.2] │·
                                                                                                                                                                                                                   │·
TASK [libvirt/setup/overcloud : Resize undercloud image (create target image)] ************************************************************************************************************************************│·
changed: [127.0.0.2] │·
                                                                                                                                                                                                                   │·
TASK [libvirt/setup/overcloud : Resize undercloud image (call virt-resize)] ***************************************************************************************************************************************│·
fatal: [127.0.0.2]: FAILED! => {"changed": false, "cmd": "virt-resize --expand /dev/sda1 /var/tmp/wes/undercloud.qcow2 /var/tmp/wes/undercloud-resized.qcow2", "msg": "[Errno 2] No such file or directory", "rc": │·
2} │·
        to retry, use: --limit @/var/tmp/wes/tripleo-quickstart/playbooks/libvirt-nodepool.retry │·
                                                                                                                                                                                                                   │·
PLAY RECAP ********************************************************************************************************************************************************************************************************│·
127.0.0.2 : ok=41 changed=18 unreachable=0 failed=1 │·
                                                                                                                                                                                                                   │·
[cgoncalves@tunafish ~]$ ls /var/tmp/wes/undercloud-resized.qcow2 │·
/var/tmp/wes/undercloud-resized.qcow2 │·
[cgoncalves@tunafish ~]$ ll /var/tmp/wes/ │·
total 852436 │·
drwxrwxr-x. 12 cgoncalves cgoncalves 4096 Sep 5 19:41 tripleo-quickstart │·
drwxrwxr-x. 9 cgoncalves cgoncalves 4096 Sep 5 19:41 tripleo-quickstart-extras │·
-rw-r--r--. 1 root root 872677376 Sep 5 19:42 undercloud.qcow2 │·
-rw-r--r--. 1 root root 198144 Sep 5 19:42 undercloud-resized.qcow2 │·
drwxrwxr-x. 6 cgoncalves cgoncalves 69 Sep 5 19:41 venv_ansible │·
-rw-rw-r--. 1 cgoncalves cgoncalves 21 Sep 5 19:41 virthost │·
-rw-r--r--. 1 root root 215 Sep 5 19:42 volume_pool.xml │·
[cgoncalves@tunafish ~]$ # why is that root? │·
[cgoncalves@tunafish ~]$ # that is the issue │·
[cgoncalves@tunafish ~]$ # hmm I'd say so too. AFK now │·
[cgoncalves@tunafish ~]$ # /me opens bug and will fix

The root cause appears to be from [1], where a simple cp command is used to copy the image from cache.

[1] http://git.openstack.org/cgit/openstack/tripleo-quickstart/tree/roles/fetch-images/tasks/fetch.yml#n184