We were setting IsUp for both the ifinfomsg::ifi_flags field and
IFLA_OPER_STATE message. Turns out the second matches the "RUNNING"
state that ifconfig used to return (IFF_RUNNING from SIOCIFFLAGS).
Example:
$ ip link show vboxnet0
4: vboxnet0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT group default qlen 1000
link/ether 0a:00:27:00:00:00 brd ff:ff:ff:ff:ff:ff
$ ifconfig vboxnet0
vboxnet0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
ether 0a:00:27:00:00:00 txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
In this example, ifconfig is not showing "RUNNING", so its "UP" matches
iproute2's in the <> section (that's the interface's ifi_flags). In an
interface that ifconfig shows RUNNING, iproute2 will show "state UP",
which is the IFLA_OPER_STATE.
Exception: looks like the loopback has IF_OPER_UNKNOWN.
Change-Id: Ic90d8429a0eb4837971dfffd1664bfc3f4b4e030
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
7507d87285