From c9dca822c72914ff33593b12f9fb229f0c0afd47 Mon Sep 17 00:00:00 2001
From: Jian Yang <jianyang@google.com>
Date: Mon, 1 Feb 2021 15:34:45 -0800
Subject: [PATCH] net-loopback: set lo dev initial state to UP

Traditionally loopback devices come up with initial state as DOWN for
any new network-namespace. This would mean that anyone needing this
device would have to bring this UP by issuing something like 'ip link
set lo up'. This can be avoided if the initial state is set as UP.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: Jian Yang <jianyang@google.com>
Link: https://lore.kernel.org/r/20210201233445.2044327-1-jianyang.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/net/loopback.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c
index a1c77cc00416..24487ec17f8b 100644
--- a/drivers/net/loopback.c
+++ b/drivers/net/loopback.c
@@ -219,6 +219,12 @@ static __net_init int loopback_net_init(struct net *net)
 
 	BUG_ON(dev->ifindex != LOOPBACK_IFINDEX);
 	net->loopback_dev = dev;
+
+	/* bring loopback device UP */
+	rtnl_lock();
+	dev_open(dev, NULL);
+	rtnl_unlock();
+
 	return 0;
 
 out_free_netdev:
-- 
2.50.1