lkml.org 
[lkml]   [2009]   [Apr]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: attempt to scan fails (device busy) if essid/ssid was changed recently
From
Date
On Tue, 2009-04-07 at 15:51 +0300, Maxim Levitsky wrote:

> > > I noticed that always first attempt at scan fails when NM asks for scan.
> > > I also noticed that this happens with quite recent kernels (I think
> > > 2,6.28) didn't have this behavior.
> >
> > I'm pretty sure it did.

> I am sure that on older kernel there was no -EBUSY error returned to
> userspace. It probably just stalled the client.

Can't imagine it did, maybe it just dropped the request though without
indicating an error.

> > > Looking a bit deeper I discovered that each time NM disconnects from a
> > > networks it sets random ssid/essid to the card (using wireless
> > > extensions)
> >
> > This forces a scan
> >
> > > After that scan fails for some time.
> > >
> > > as a NM free example you can run
> > >
> > > iwconfig wlan0 essid dummy
> > > iwlist scan
> >
> > and then this fails with EBUSY.
> Thanks for explanation.
> Since NM has its reasons to clear essid (to prevent unwanted
> association), then what can be done to prevent this (and still use
> wireless extensions, since nl80211 support isn't yet mature)?

Nothing. Wext sucks, news at 11, yadda.

johannes
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2009-04-07 15:03    [W:0.048 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site