Subject: [PATCH AUTOSEL 6.0 09/13] net: loopback: use NET_NAME_PREDICTABLE for name_assign_type

From: Sasha Levin <[email-masked]>
Date: Tue, 6 Dec 2022 04:49:12 -0500

From: Rasmus Villemoes <[email-masked]>

[ Upstream commit 31d929de5a112ee1b977a89c57de74710894bbbf ]

When the name_assign_type attribute was introduced (commit
685343fc3ba6, "net: add name_assign_type netdev attribute"), the
loopback device was explicitly mentioned as one which would make use
of NET_NAME_PREDICTABLE:

    The name_assign_type attribute gives hints where the interface name of a
    given net-device comes from. These values are currently defined:
...
      NET_NAME_PREDICTABLE:
        The ifname has been assigned by the kernel in a predictable way
        that is guaranteed to avoid reuse and always be the same for a
        given device. Examples include statically created devices like
        the loopback device [...]

Switch to that so that reading /sys/class/net/lo/name_assign_type
produces something sensible instead of returning -EINVAL.

Signed-off-by: Rasmus Villemoes <[email-masked]>
Reviewed-by: Jacob Keller <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 drivers/net/loopback.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c
index 14e8d04cb434..2e9742952c4e 100644
--- a/drivers/net/loopback.c
+++ b/drivers/net/loopback.c
@@ -211,7 +211,7 @@ static __net_init int loopback_net_init(struct net *net)
 	int err;
 
 	err = -ENOMEM;
-	dev = alloc_netdev(0, "lo", NET_NAME_UNKNOWN, loopback_setup);
+	dev = alloc_netdev(0, "lo", NET_NAME_PREDICTABLE, loopback_setup);
 	if (!dev)
 		goto out;
 
-- 
2.35.1