eth.py: nic constructor generates eth interface

experiments/simbricks/orchestration/system/eth.py

@@ -44,7 +44,7 @@ class EthSimpleNIC(base.Component):
     def __init__(self, s: base.System) -> None:
         super().__init__(s)
         self._ip = None
-        self._eth_if: EthInterface | None = None
+        self._eth_if = EthInterface(self)
 
     def add_ipv4(self, ip: str) -> None:
         assert self._ip is None

experiments/simbricks/orchestration/system/nic.py

@@ -30,7 +30,7 @@ class SimplePCIeNIC(pcie.PCIeSimpleDevice, eth.EthSimpleNIC):
         super().__init__(s)
 
     def interfaces(self) -> list[base.Interface]:
-        return [self.pci_if, self.eth_if]
+        return [self._pci_if, self._eth_if]
 
     def add_if(self, interface: eth.EthInterface | pcie.PCIeDeviceInterface) -> None:
         match interface: