2013-06-10 14:30:22

by François Ravaillac

[permalink] [raw]
Subject: [DEFECT] iw: No output if passive scanning is requested


Using b43 driver with newer kernels (namely, 3.8-1-686-pae from Debian
and 3.10.0-rc4 from git) it isn't possible to perform passive scanning
(in 2.4GHz band) using 'iw' tool. The command 'iw dev wlan0 scan
passive' doesn't print any output. At the same time, a usual scan with
sending probe requests ('iw wlan0 scan' or 'iwlist wlan0 scan') does
work as expected.

The radio module I'm using is
05:00.0 Network controller [0280]: Broadcom Corporation BCM4312
802.11b/g LP-PHY [14e4:4315] (rev 01)

Copy of dmesg, lspci, lsmod, 'iw phy0 info' outputs and kernel config file
is attached.


P.S. I'm not a developer nor programmer, but I'm ready to help to make
linux better :)

--

Ravaillac


2013-06-10 14:54:10

by Rafał Miłecki

[permalink] [raw]
Subject: Re: [DEFECT] iw: No output if passive scanning is requested

2013/6/10 François Ravaillac <[email protected]>:
> Using b43 driver with newer kernels (namely, 3.8-1-686-pae from Debian
> and 3.10.0-rc4 from git) it isn't possible to perform passive scanning
> (in 2.4GHz band) using 'iw' tool. The command 'iw dev wlan0 scan
> passive' doesn't print any output. At the same time, a usual scan with
> sending probe requests ('iw wlan0 scan' or 'iwlist wlan0 scan') does
> work as expected.
>
> The radio module I'm using is
> 05:00.0 Network controller [0280]: Broadcom Corporation BCM4312
> 802.11b/g LP-PHY [14e4:4315] (rev 01)
>
> Copy of dmesg, lspci, lsmod, 'iw phy0 info' outputs and kernel config file
> is attached.
>
>
> P.S. I'm not a developer nor programmer, but I'm ready to help to make
> linux better :)

Hm, this is very interesting. Recently I've discovered problem with
finding AP working on channel 13. It turned out to be a regression
caused by
> Scanning regression since "cfg80211: use DS or HT operation IEs to determine BSS channel"
http://lists.infradead.org/pipermail/b43-dev/2013-March/003003.html

I think it can be related. I'll try to take a look at this in free
time, but don't promise anything soon. Thanks for your report anyway.

--
Rafał