diff --git a/src/net/interface_plan9.go b/src/net/interface_plan9.go
index 1295017a1b..31bbaca467 100644
--- a/src/net/interface_plan9.go
+++ b/src/net/interface_plan9.go
@@ -68,8 +68,8 @@ func readInterface(i int) (*Interface, error) {
 	}
 	ifc.MTU = mtu
 
-	// Not a loopback device
-	if device != "/dev/null" {
+	// Not a loopback device ("/dev/null") or packet interface (e.g. "pkt2")
+	if stringsHasPrefix(device, netdir+"/") {
 		deviceaddrf, err := open(device + "/addr")
 		if err != nil {
 			return nil, err