From: Petr Machata Date: Tue, 9 Feb 2021 17:52:04 +0000 (+0100) Subject: Revert "net-loopback: set lo dev initial state to UP" X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=1edb5cbf49a7464a575966ad6f48b3876fb64f63;p=linux.git Revert "net-loopback: set lo dev initial state to UP" In commit c9dca822c729 ("net-loopback: set lo dev initial state to UP"), linux started automatically bringing up the loopback device of a newly created namespace. However, an existing user script might reasonably have the following stanza when creating a new namespace -- and in fact at least tools/testing/selftests/net/fib_nexthops.sh in Linux's very own testsuite does: # set -e # ip netns add foo # ip -netns foo addr add 127.0.0.1/8 dev lo # ip -netns foo link set lo up # set +e This will now fail, because the kernel reasonably rejects "ip addr add" of a duplicate address. The described change of behavior therefore constitutes a breakage. Revert it. Fixes: c9dca822c729 ("net-loopback: set lo dev initial state to UP") Signed-off-by: Petr Machata Reviewed-by: Jakub Kicinski Signed-off-by: David S. Miller --- diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c index 24487ec17f8b1..a1c77cc004165 100644 --- a/drivers/net/loopback.c +++ b/drivers/net/loopback.c @@ -219,12 +219,6 @@ 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: