wlan: UP but not RUNNING ?

This is on 14.3.
I have configured two VAPs, the configuration is almost identical except for SSID.
hostapd-s for both interfaces are also running.
Both interfaces are UP, both have status running, but one doesn't have RUNNING 
in its flags.

What does that mean?

wlan0: flags=8903<UP,BROADCAST,PROMISC,SIMPLEX,MULTICAST> metric 0 mtu 1500
         options=0
...
         parent interface: ath0
         media: IEEE 802.11 Wireless Ethernet autoselect mode 11ng <hostap>
         status: running

wlan1: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> metric 0 mtu 1500
         options=0
...
         parent interface: ath0
         media: IEEE 802.11 Wireless Ethernet autoselect mode 11ng <hostap>
         status: running


-- 
Andriy Gapon