Questions About Intel Wireless 4965

Lenovo T61 laptop running openSUSE 12.1 with KDE

Here’s the output on the intel 4965 chipset from lspci

03:00.0 Network controller: Intel Corporation PRO/Wireless 4965 AG or AGN [Kedron] Network Connection (rev 61)

My problem is the iwl4965 driver doesn’t perform well. Out of the box iwl4965 works, but it is unusable. It’s “slow” and “hangs”. Reading around has confused me as to what driver options I have. Three driver names I come across are iwl4965, iwlagn, and iwlwifi. I compiled compat wireless to see if that would help, but no. Actually, compat wireless disabled my use of iwl4965 and put a “preference” on iwlagn. The odd bit is that there is no driver named iwlagn under the updates directory, but there is under the kernel directory, which is what gets loaded. The problem with iwlagn is that I haven’t been able to get it to work.

There’s a program named iwl-load that toggles between iwlagn and iwl4965. To effectively switch back to using iwl4965 I had to find the module under the updates directory, remove the .ignore ending, and then run “iwl-load iwl4965”. If I didn’t rename the iwl4965 module under updates before running iwl-load I would then need to run “depmod -a”. Then I could “modprobe iwl4965”.

Here’s the output from running “iwl-load iwlagn”

linux-mvg4:~ # iwl-load iwlagn
Unloading ...
2 iwl4965 modules found we'll disable all of them
Disabling iwl4965 (1) ...WARNING: -e needs -E or -F
[ERROR] Module is still being detected:

updates/drivers/net/wireless/iwlegacy/iwl4965.ko
Disabling iwl4965 (2) ...WARNING: -e needs -E or -F
        [OK]    Module disabled:
updates/drivers/net/wireless/iwlegacy/iwl4965.ko
Enabling iwlagn ...WARNING: -e needs -E or -F
        [OK]    Module renamed but another module file is being preferred
Renamed module:         /lib/modules/3.1.0-1.2-desktop/kernel/drivers/net/wireless/iwlwifi/iwlagn.ko
Preferred module:       kernel/drivers/net/wireless/iwlwifi/iwlagn.ko
FATAL: Error inserting iwlagn (/lib/modules/3.1.0-1.2-desktop/kernel/drivers/net/wireless/iwlwifi/iwlagn.ko): Invalid argument
iwlagn loaded successfully
linux-mvg4:~ # 

There’s lots of output in dmesg similar to the following

 2600.115453] iwlagn: disagrees about version of symbol ieee80211_iter_keys
 2600.115455] iwlagn: Unknown symbol ieee80211_iter_keys (err -22)

If I remove the wireless drivers and “modprobe iwlwifi” I get no errors, but I don’t have a wireless interface either. In dmesg I see the following

Jan  6 19:42:25 linux-mvg4 kernel:  6905.953349] cfg80211: Calling CRDA to update world regulatory domain
Jan  6 19:42:25 linux-mvg4 kernel:  6905.962892] cfg80211: World regulatory domain updated:
Jan  6 19:42:25 linux-mvg4 kernel:  6905.962897] cfg80211:     (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Jan  6 19:42:25 linux-mvg4 kernel:  6905.962900] cfg80211:     (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Jan  6 19:42:25 linux-mvg4 kernel:  6905.962903] cfg80211:     (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Jan  6 19:42:25 linux-mvg4 kernel:  6905.962905] cfg80211:     (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
Jan  6 19:42:25 linux-mvg4 kernel:  6905.962908] cfg80211:     (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Jan  6 19:42:25 linux-mvg4 kernel:  6905.962911] cfg80211:     (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Jan  6 19:42:25 linux-mvg4 kernel:  6905.991360] Intel(R) Wireless WiFi Link AGN driver for Linux, in-tree:d
Jan  6 19:42:25 linux-mvg4 kernel:  6905.991363] Copyright(c) 2003-2011 Intel Corporation

I’m stuck on what to do next. Maybe the performance of iwl4965 can be tweaked? What steps do I take to get iwlagn to work? And what about iwlwifi? Does anyone have experience with intel wireless chipsets who can help me on this? Instead of plugging in a usb wlan adapter I would rather try getting this one to work. I also have a t60 laptop with an intel 3945 chipset. That one works well with the iwl3945 driver. How odd.

Here’s a link to info on the driver for this class of Intel wireless chips:
http://downloadcenter.intel.com/Detail_Desc.aspx?agr=Y&DwnldID=17045&ProdId=3229&lang=eng&OSVersion=Linux*&DownloadType=Drivers
Not that it did much for me–I’m having the same problems with a Wireless-N 1000 chip in a Toshiba Satellite notebook.
The FAQ for Linux support of Intel wireless: Wireless Networking — Linux support for Intel
And what does the .ko mean in iwlagn.ko?

On 03/16/2012 01:16 PM, konsultor wrote:
>
> Here’s a link to info on the driver for this class of Intel wireless
> chips:
> http://tinyurl.com/8ywhum4
> Not that it did much for me–I’m having the same problems with a
> Wireless-N 1000 chip in a Toshiba Satellite notebook.
> The FAQ for Linux support of Intel wireless: ‘Wireless Networking
> — Linux support for Intel’
> (http://www.intel.com/support/wireless/sb/CS-006408.htm)
> And what does the .ko mean in iwlagn.ko?

Kernel Object. That is the extension for all modules in kernel 2.6.0 and beyond.

I’m curious what issues you are having with your chip, I’m using the same driver with superlative performance… at least after I modified my TCP/IP configuraiton. I’ve noticed that my wireless seems to far outperform just about anyone else in a public hotspot.

Recommend you undo any changes you may have made, go back to the original driver and take a look at this paper I’ve written…

Optimize and Fix your Network Connection - Su Networking Technical

Note that it was <very important> for me to change the TCP/IP Congestion Control algorithm, and because I’m often opening up numerous full and half-open network connections I also benefit from enlarging my buffers from the default values.

HTH,
TS