From ae330408d802df5a15bda8c10094197c4d67eb16 Mon Sep 17 00:00:00 2001
From: Roopa Prabhu <roopa@cumulusnetworks.com>
Date: Tue, 29 Nov 2016 19:55:32 -0800
Subject: [PATCH] iface: add support for ifaceLinkPrivFlags.LOOPBACK

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
---
 ifupdown/iface.py        | 1 +
 ifupdown/ifupdownmain.py | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/ifupdown/iface.py b/ifupdown/iface.py
index 4c2f6e0..98a3c89 100644
--- a/ifupdown/iface.py
+++ b/ifupdown/iface.py
@@ -63,6 +63,7 @@ class ifaceLinkPrivFlags():
     BRIDGE_VLAN_AWARE = 0x01000
     BRIDGE_VXLAN =      0x10000
     ADDRESS_VIRTUAL_SLAVE = 0x100000
+    LOOPBACK = 0x1000000
 
     @classmethod
     def get_str(cls, flag):
diff --git a/ifupdown/ifupdownmain.py b/ifupdown/ifupdownmain.py
index 96f89ee..697118d 100644
--- a/ifupdown/ifupdownmain.py
+++ b/ifupdown/ifupdownmain.py
@@ -493,6 +493,9 @@ class ifupdownMain(ifupdownBase):
             upperifaceobj.link_type = ifaceLinkType.LINK_NA
             ifaceobj.link_type = ifaceLinkType.LINK_NA
 
+        if not ifaceobj.link_kind and ifaceobj.name == "lo":
+            ifaceobj.link_privflags |= ifaceLinkPrivFlags.LOOPBACK
+
     def dump_iface_dependency_info(self):
         """ debug funtion to print raw dependency 
         info - lower and upper devices"""