Re: periodic_update(): Roamed ...

[Howard Chu <hyc symas com>]

Alexander Sack wrote:
> On Mon, Apr 20, 2009 at 03:37:20PM -0700, Howard Chu wrote:
> > Howard Chu wrote:
> > > This is probably more related to the ath9k driver, but I wanted to start here
> > > in case anyone is familiar with it. I've been seeing this for the past couple
> > > months, and I just now rebuilt NM fresh from git and it's still happening:
> >
> > I seem to have ruled out the driver; doing a kill -9 on NetworkManager so
> > it doesn't have the opportunity to tear down the connection on exit,
> > shows that the wifi connection works perfectly once NetworkManager is
> > gone. No disassociation messages in dmesg, no pauses in ssh sessions,
> > etc.
>
> I would think that the driver doesn't like background scanning. This
> has been reported in launchpad bug 291760 where the initial report
> mentions that "he network manager roames to a "none" bssid and back,
> this happens in more or less two minute" which coincidentially matches
> the max scan timeout NM uses (120 seconds).

Thanks for the reminder, I had forgotten about that bug report and the last 
time I had encountered this problem. As I mentioned in January (and forgot)

http://mail.gnome.org/archives/networkmanager-list/2009-January/msg00107.html

restoring the "madwifi hack" to NM/src/nm-device-wifi.c makes the problem go 
away for me. I've posted the patch to the launchpad bug. I.e., reverting this 
commit:

commit 98f392b085985a75274fe02ec8aa92f4ac0d8a80
Author: Dan Williams <dcbw redhat com>
Date: Sat Oct 11 18:32:24 2008 +0000

    2008-10-11 Dan Williams <dcbw redhat com>

        * src/nm-device-wifi.c
                - (can_scan): remove old madwifi hack for not scanning while

--
  -- Howard Chu
  CTO, Symas Corp.           http://www.symas.com
  Director, Highland Sun     http://highlandsun.com/hyc/
  Chief Architect, OpenLDAP  http://www.openldap.org/project/