root@server:~# hostapd -dd /etc/hostapd/hostapd.conf
Configuration file: /etc/hostapd/hostapd.conf
nl80211: Add own interface ifindex 6
nl80211: Failed to set interface 6 to mode 3: -95 (Operation not supported)
nl80211: Failed to set interface 6 to mode 3: -95 (Operation not supported)
nl80211: Interface mode change to 3 from 0 failed
nl80211: Failed to set interface wlan0 into AP mode
nl80211 driver initialization failed.
ELOOP: remaining socket: sock=4 eloop_data=0x9304c0 user_data=0x930c80 handler=0x433880
ELOOP: remaining socket: sock=6 eloop_data=0x9331c0 user_data=(nil) handler=0x43cc10

root@server:~# dmesg
[...]
ADDRCONF(NETDEV_UP): wlan0: link is not ready

root@server:~# cat /etc/hostapd/hostapd.conf
interface=wlan0
driver=nl80211
ssid=testubu
channel=1
hw_mode=g
ieee80211n=1

root@server:~# lsmod | grep iwl
iwl4965               132375  0
iwl_legacy             83487  1 iwl4965
mac80211              462092  2 iwl4965,iwl_legacy
cfg80211              199630  3 iwl4965,iwl_legacy,mac80211

root@server:~#