authentication timeouts with ath(4) in hostap mode

[Petar Bogdanovic]

Hi,

I'm using an alix2c0 board with two winstron CM9 ath(4)-cards and
FreeBSD 7:

	ifconfig ath0 (...) mediaopt hostap mode 11a channel 36 ssid sn.a -bgscan
	ifconfig ath1 (...) mediaopt hostap mode 11g channel 11 ssid sn.g -bgscan


When I try to raise the traffic (i.e. dd | ssh AP dd) my Linux
wpa_supplicant drops the connection and has to reassociate. This however
does not work immediately; The supplicant fails a few times before
reconnecting:

	<2>CTRL-EVENT-CONNECTED - Connection to 00:0b:0b:06:0d:09 completed (reauth) [id=0 id_str=]
	<2>CTRL-EVENT-DISCONNECTED - Disconnect event - remove keys
	<2>Trying to associate with 00:0b:0b:06:0d:09 (SSID='sn.a' freq=5320 MHz)
	<2>Authentication with 00:0b:0b:06:0d:09 timed out.
	<2>Trying to associate with 00:0b:0b:06:0d:09 (SSID='sn.a' freq=5320 MHz)
	<2>Authentication with 00:0b:0b:06:0d:09 timed out.
	<2>Trying to associate with 00:0b:0b:06:0d:09 (SSID='sn.a' freq=5320 MHz)
	<2>Authentication with 00:0b:0b:06:0d:09 timed out.
	<2>Trying to associate with 00:0b:0b:06:0d:09 (SSID='sn.a' freq=5320 MHz)
	<2>Authentication with 00:0b:0b:06:0d:09 timed out.
	<2>Trying to associate with 00:0b:0b:06:0d:09 (SSID='sn.a' freq=5320 MHz)
	<2>Authentication with 00:0b:0b:06:0d:09 timed out.
	<2>Trying to associate with 00:0b:0b:06:0d:09 (SSID='sn.a' freq=5320 MHz)
	<2>Authentication with 00:0b:0b:06:0d:09 timed out.
	<2>Trying to associate with 00:0b:0b:06:0d:09 (SSID='sn.a' freq=5320 MHz)
	<2>Associated with 00:0b:0b:06:0d:09
	<2>WPA: Key negotiation completed with 00:0b:0b:06:0d:09 [PTK=CCMP GTK=CCMP]
	<2>CTRL-EVENT-CONNECTED - Connection to 00:0b:0b:06:0d:09 completed (reauth) [id=0 id_str=]


This happens more on the 11a than on the 11g network. When I'm next to
the AP, the timeouts are almost gone but they still happen. (My laptop
is just one room away from the AP). Here is the athstats-output of ath0
(11a):

	# ./athstats -i ath0
	481546 data frames received
	330669 data frames transmit
	13395 tx frames with an alternate rate
	78558 long on-chip tx retries
	1431 tx failed 'cuz too many retries
	36M current transmit rate
	78 tx management frames
	3 tx frames discarded prior to association
	45 tx frames with no ack marked
	2894 rx failed 'cuz of bad CRC
	2 rx failed 'cuz decryption
	92711 rx failed 'cuz of PHY err
	    92708 OFDM timing
	    3 OFDM restart
	318332 beacons transmitted
	1111 periodic calibrations
	2 rfgain value change
	22 rssi of last ack
	23 avg recv rssi
	-96 rx noise floor
	2530 switched default/rx antenna
	Antenna profile:
	[1] tx   173364 rx   123068
	[2] tx   155874 rx   358671


All this is well known to me, since I had NetBSD running on this device
for months and it suffered the same problems -- it was even worse, the
timeouts occured every few minutes. Back then, it seemed that ath had
some interrupt problems:

	ath0: device timeout

as David Young from NetBSD noticed in his mail some time ago:

	http://mail-index.netbsd.org/tech-net/2007/11/29/0001.html


FreeBSD doesn't seem to have this `device timeouts'. I don't see any in
/var/log/messages and there are none when I'm connected to the device
over a serial port.

I'm a bit lost here, but ready to debug if someone knows more.


Thanks,

Petar