Wireless mystery with 2.6.31 kernel

February 03, 2010 — BarryK

My Acer 3681WXMi laptop has inbuilt wireless that uses the ath5k kernel module. It used to work, however with Quirky and the 2.6.31.5 kernel it doesn't.

In the Network Wizard, when I choose to scan for neworks, an error message comes up that 'ifconfig wlan0 up' failed, with this error:

ifconfig: SIOCSIFFLAGS: Unknown error 132

I googled around, and there are many wireless problems with recent kernels. My particular problem seems to have something to do with the 'rfkill.ko' kernel module, which is now a dependency of the wireless kernel modules.

There is a utility called 'rfkill' that queries the state of a wireless interface. I ran it:

# rfkill list
0: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no

However, after I had done the scan with the Network Wizard, it returns this:

# rfkill list
0: phy0: Wireless LAN
Soft blocked: no
Hard blocked: yes

"Hard blocked" means that there is a hardware switch on my laptop that has turned off the wireless interface. That is just plain incorrect.

I found a "fix" posted in a forum thread discussing the same problem with the 'ath9k' driver. I applied it to my ath5k:

# rmmod ath5k
# rfkill block wifi
# rfkill unblock wifi
# modprobe ath5k
# ifconfig wlan0 up

Somehow, the above clears the problem. But then, running Network Wizard and the problem comes back. So, I had a little play with /usr/sbin/wag-profiles.sh (part of Network Wizard) and modified the cleanUpInterface function:

cleanUpInterface(){

	# put interface down

	#ifconfig "$1" down

	killDhcpcd "$1"

	# kill wpa_supplicant

	killWpaSupplicant "$1"

	# clean up some wireless stuff (taken from wifi-radar)

	if [ "$IS_WIRELESS" = "yes" ] ; then

	  iwconfig "$1" essid off

	  iwconfig "$1" key off

	  iwconfig "$1" mode managed # auto doesn't exist anymore??

	  iwconfig "$1" channel auto

	fi

	# put interface down

	ifconfig "$1" down

	# reset ip address (set a false one)

	ifconfig "$1" 0.0.0.0

	# stop dhcpcd 

	#killall dhcpcd 2>/dev/null

	# flush routing table

	#ip route flush dev "$1"

	# bring interface up again

	#ifconfig "$1" up

	

	#100202

	ERROR="`ifconfig "$1" up 2>&1`"

	if [ "$ERROR" ];then

	 case $1 in

	  wlan*)

	   if [ "`echo "$ERROR" | grep 'ifconfig: SIOCSIFFLAGS: Unknown error 132'`" != "" ];then

	    rmmod $INTMODULE

	    rfkill block wifi

	    rfkill unblock wifi

	    modprobe $INTMODULE

	    ERROR="`ifconfig "$1" up 2>&1`"

	   fi

	  ;;

	 esac

	fi

	if [ "$ERROR" ];then

	  giveErrorDialog "${L_MESSAGE_Failed_To_Raise_p1}${1}${L_MESSAGE_Failed_To_Raise_p2} ifconfig $1 up

$L_MESSAGE_Failed_To_Raise_p3

$ERROR

"

	  return 1

	fi



	return $?

} # end cleanUpInterface

Hmmm, now there is no error message, but it reports no networks found (there is one, about 1 foot away from my laptop!).

I'm far from an expert on networking, and I have left development of these wizards to others. I have messed around a bit, but that's enough.

Now plugging in my USB wireless, which does work with the Wizard.

The Arch Linux guys have been discussing this problem, ath5k/ath9k and 2.6.31.x:

http://bbs.archlinux.org/viewtopic.php?id=81930

...seem to be quite a mess.

Hmmm, I wonder if the 2.6.33 kernel has improved this situation? I wonder if I can/should disable 'rfkill' in the kernel pre-compile configuration?

Rfkill utility links
http://linuxwireless.org/en/users/Documentation/rfkill
http://wireless.kernel.org/download/rfkill/

Comments

maybe try updating the BIOS
Username: Jemimah
I had this problem on my Eee 1005HA (ath9k), but only with a specific BIOS version. I had upgraded because they claimed a fix for suspend issues, but the fix was a lot worse than the problem. :( Luckily, I've now grabbed the very latest BIOS, and the rfkill switch now works correctly.

Tags: quirky