Add PCI passthrough device to a VM using pyvmomi

gistfile1.py

def add_pci_to_vm(host_object, vm_object, host_pci_dev):
    """
    host_pci_dev must be one of the devices from the host_object.hardware.pciDevice list
    which is configured as a PCI passthrough device
    """
    pci_passthroughs = vm_object.environmentBrowser.QueryConfigTarget(host=None).pciPassthrough
    systemid_by_pciid = {item.pciDevice.id: item.systemId for item in pci_passthroughs}

    if host_pci_dev.id not in systemid_by_pciid:
        raise Exception("Not a passthrough device")

    # According to the documentation, the deviceId is a signed short but the server expects the PCI device ID
    # to be unsigned. TODO the modulu here is because of this, but I think it's not needed
    deviceId = hex(host_pci_dev.deviceId % 2**16).lstrip('0x')
    backing = vim.VirtualPCIPassthroughDeviceBackingInfo(deviceId=deviceId,
        id=host_pci_dev.id,
        systemId=systemid_by_pciid[host_pci_dev.id],
        vendorId=host_pci_dev.vendorId,
        deviceName=host_pci_dev.deviceName)

    hba_object = vim.VirtualPCIPassthrough(key=-100, backing=backing)

    new_device_config = vim.VirtualDeviceConfigSpec(device=hba_object)
    new_device_config.operation = "add"

    vm_object.ReconfigVM_Task(spec=new_device_config)

Hi Guys,
I am wondering How I can remove PCI card in a similar way you are discussing here,
according to https://github.com/vmware/pyvmomi/blob/master/docs/vim/vm/device/VirtualDeviceSpec/Operation.rst
it seem strait forward that the only modification needed is "remove" instead of the "add"
but I get the notorious, Invalid configuration for device '0',
What can I be missing?
regards.

EDIT

---

One way to remove vm pci's card is as follows:

spec = vim.vm.ConfigSpec()

spec.deviceChange = []

for dev in vm.config.hardware.device:

    if isinstance(dev, vim.vm.device.VirtualPCIPassthrough):
        vdspec = vim.vm.device.VirtualDeviceSpec()
        vdspec.operation='remove'
        vdspec.device = dev
        spec.deviceChange.append(vdspec)
the_task = vm.ReconfigVM_Task(spec=spec)

Hello I'm not able to configure how to set memory reservation through the code so that my vm can start automatically through code.
Any help would be awesome.
regards.
EDIT
I figured it out how to set reserved memory.
For anyone wants to know add
vmConfigSpec.memoryReservationLockedToMax = True above vm_object.ReconfigVM_Task(spec=vmConfigSpec)
Cheers!

Basic question but How to set values of host_object, vm_object, host_pci_dev

To get vm_object you can take a look at the pyvmomi community samples, or infi.pyvmomi_wrapper. Make sure it is not None. host_object can be the VM's runtime host - vm.summary.runtime.host. For host_pci_dev see the docstring.

what's docstring?

Does anyone know how to list VirtualPCIPassthrough's all VMs?

How to plugin dynamic Passthrough device to a VM using pyvmomi sdk? Does anyone know anything about this?