nova-manage placement heal_allocations does not support instances with VGPU or Cyborg device profile request

[Balazs Gibizer]

The nova-manage placement heal_allocations tool predates nested allocation support in nova. It gained explicit support for nested allocation only in case if the nested resources are coming from the port resource request [1]. If the resource request are coming from the flavor extra_specs (e.g. resources:VGPU=1) then the tool assumes that such resource can be fulfilled from the root resource provider[2][3]. This is obviously wrong for the VGPU resource that are provided on nested resource providers. Also [3] does not resolve cyborg device profiles to request groups so that request is also ignored.

As --force flag allows recreating instance allocations even if the tool does not detect a missing allocation using the tool on VGPU and Cyborg instances could result in loosing otherwise correct resource allocations. Loosing such resource allocation can lead to physical resource over-allocation later.

[1] https://github.com/openstack/nova/blob/2ffd9738602531e93495a1feca76bbb687c3e72c/nova/cmd/manage.py#L1814
[2] https://github.com/openstack/nova/blob/2ffd9738602531e93495a1feca76bbb687c3e72c/nova/cmd/manage.py#L1700
[3] https://github.com/openstack/nova/blob/2ffd9738602531e93495a1feca76bbb687c3e72c/nova/scheduler/utils.py#L607-L614