Why pci passthrough instance is getting lauched on wrong host aggregate ?

Issue

• While trying to launch a pci passthrough instance, why it's getting started on wrong host aggregate ?

The host we want to start the instance on is in a host aggregate that has the following metadata:

    1_to_1 = true
    pci_passthrough:alias = lsi_raid1:1
    availability_zone = nova

It is actually launched on a host that is in a host aggregate with the following metadata:

    1_to_1 = true
    availability_zone = nova
    ram_allocation_ratio = 1.2
    cpu_allocation_ratio = 1

The flavour has the following metadata:

    1_to_1 = true
    pci_passthrough:alias = lsi_raid1:1

• Why it's not respecting AggregateInstanceExtraSpecsFilter filter set in nova.conf file ?

scheduler_default_filters=AggregateInstanceExtraSpecsFilter,RetryFilter,AvailabilityZoneFilter,AggregateRamFilter,AggregateCoreFilter,ComputeFilter,ImagePropertiesFilter,ServerGroupAntiAffinityFilter,ServerGroupAffinityFilter,PciPassthroughFilter