Re: carl9170: Unintentional transmission in monitor mode?

[Johannes Berg <johannes@sipsolutions.net>]

On Thu, 2012-08-09 at 21:43 +0200, Christian Lamparter wrote:
> On Thursday, August 09, 2012 06:54:34 PM Marco Fonseca wrote:
> > Hello All,
> > 
> > I've noticed unexpected transmissions from the AR9170 while in monitor mode
> > and using tcpdump (and sometimes without tcpdump running).  These
> > transmissions degrade (pretty significantly) performance of other STA/AP on
> > the channel (as seen by iperf going from 60mbit/s to almost nill).  As best I
> > can tell these transmissions never coalesces into an actual frame in the air
> > (at least not one I'm able to pick up with a second different adapter in
> > monitor mode).
> > 
> > Are there any known reasons/bugs on this?  Is there anyway to completely
> > silence the transmitter of the AR9170 while still allowing reception?
> > 
> yes. <http://www.spinics.net/lists/linux-wireless/msg88896.html>
> 
> a solution is described in:
> <http://www.spinics.net/lists/linux-wireless/msg89279.html>
> 
> (iw dev wlanX set monitor none - if I'm not mistaken)

I've seen this before too -- what flag causes the issue, and why?

johannes