[ath9k-devel] Unrealistic RSSI values being reported

[Daniel Smith <viscous.liquid@gmail.com>]

On 11/3/2011 7:10 PM, Mohammed Shafi wrote:
> Hi Daniel,
>
> On Fri, Nov 4, 2011 at 12:58 AM, Daniel Smith<viscous.liquid@gmail.com>  wrote:
>> I recently upgraded to compat-wireless-3.1-rc8 from
>> compat-wireless-2.6.39-1-sn and have discovered an interesting behavior.
>> When in monitor mode I use the signal strength field reported in
>> radiotap and with 3.1 I am now getting a range of values. The more
>> interesting ones are all the frames reporting a signal of 110+ dBm. To
>> see what is being pulled from the descriptors I dumped rs->rs_rssi to
>> klog when the value was larger than 95. Below is a snippet showing the
>> ranging values,
> i tried with the AR9382 card in 3.1.0-wl with the attached debug
> patch, can you please give a sample log with the patch applied and
> putting the interface in monitor mode. did you print/check rs_rssi
> somewhere else?
> did you also try with the latest package
> http://linuxwireless.org/download/compat-wireless-2.6/

First I apologize as I forgot to mention I am putting the channel into 
HT40 mode and the frames coming in are non-HT as that is the stated that 
the issue was reported to me. I have not ran test yet to see if it 
occurs with the channel in HT20 and non-ht mode. Also I have one more 
test to run on compat-wireless-3.0-2 but it looks like I am not seeing 
any issue with it.

For reference here is the patch from my change, very similar to yours 
except that I didn't dump signal or noise.

@@ -1015,6 +1015,8 @@ static int ath9k_rx_skb_preprocess(struct 
ath_common *common,
         rx_status->snr = rx_stats->rs_rssi;
         rx_status->antenna = rx_stats->rs_antenna;
         rx_status->flag |= RX_FLAG_MACTIME_MPDU;
+       if (rx_stats->rs_rssi > 95 || rx_stats->rs_rssi < 0)
+               printk("[ath9k]: RSSI %hhd\n", rx_stats->rs_rssi);

         return 0;
  }

I will rerun it with your additions so you can see those values as well. 
Yes I can also test it with a nightly package to see if it has been 
resolved.

Thanks for the Help!

dps