Re: madwifi and NetworkManager

[Shaya Potter <spotter cs columbia edu>]

On Mon, 2004-11-15 at 12:35 -0500, Shaya Potter wrote:
> so I was having problems w/ NetworkManager and my madwifi using T42p, I
> noticed this thread
> 
> http://mail.gnome.org/archives/networkmanager-list/2004-November/msg00090.html
> 
> and yes, iwlist was giving me issues.  so I started instrumenting the
> driver and iwlist itself.
> 
> it appears madwifi takes a while to return, and iwlist was timing out.
> if I reset iwlist's timeouts to 2 seconds each (as opposed to 250ms and
> 100ms) it worked perfectly each time.
> 
> could it be a similiar problem w/ NetworkManager?
> 
> obviously madwifi has issues, I've set an e-mail to it's -dev mailing
> list, as dont have a clue right now about how its internals work, so
> dont know how to fix it there.

well it doesn't seem to be a madwifi issue according to the main
developer.

----
Current code + current iwlist will not work if there's a short timeout.

Applications that timeout scanning requests do so out of fear that the
driver is busted.  Typically such timeouts were chosen for 11b-only
cards where you need to scan only 3-4 channels.  For multi-mode cards
any "deadman timeouts" must be longer.  wpa_supplicant used to have a
short timeout; now it defers the decision to the driver where it knows
better.

FWIW Microsoft requires that drivers return scan results within 2
seconds (if memory serves me).
----

things I noticed with the NetworkManager code, it seems to only wait
half a second, tried changing it to 2 seconds in one place, but it
didn't seem to accomplish anything of value, so there could be other
issues.