Return-path: Received: from mail-iw0-f171.google.com ([209.85.223.171]:47641 "EHLO mail-iw0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965488AbZLHTv7 convert rfc822-to-8bit (ORCPT ); Tue, 8 Dec 2009 14:51:59 -0500 MIME-Version: 1.0 In-Reply-To: <20091208105952.3831c29b@nehalam> References: <20091207172616.7470ed2b@nehalam> <20091208142940.GB15172@tuxdriver.com> <20091208104336.3d5a7fb4@nehalam> <43e72e890912081050w265bcbc1sd1380ef52fc0799b@mail.gmail.com> <20091208105952.3831c29b@nehalam> From: "Luis R. Rodriguez" Date: Tue, 8 Dec 2009 11:51:46 -0800 Message-ID: <43e72e890912081151r11d22b77sf974fe38694308d5@mail.gmail.com> Subject: Re: wireless device and udev To: Stephen Hemminger Cc: "John W. Linville" , linux-wireless@vger.kernel.org, linux-hotplug@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Tue, Dec 8, 2009 at 10:59 AM, Stephen Hemminger wrote: > On Tue, 8 Dec 2009 10:50:30 -0800 > "Luis R. Rodriguez" wrote: > >> On Tue, Dec 8, 2009 at 10:43 AM, Stephen Hemminger >> wrote: >> > On Tue, 8 Dec 2009 09:29:40 -0500 >> > "John W. Linville" wrote: >> > >> >> On Mon, Dec 07, 2009 at 05:26:16PM -0800, Stephen Hemminger wrote: >> >> > The default udev persistent network rules based on hardware mac id doesn't >> >> > work well when multiple SSID's are created on an access-point.  The command >> >> >  iw phy phy0 interface add wlan1 type managed >> >> > >> >> > is supposed to make a device name wlan1, but udev sees that it has the same >> >> > mac address as wlan0 and gets confused leaving the device named wlan1_rename >> >> > >> >> > It looks like wlanX is breaking assumptions of existing udev persistent network >> >> > device name generation rules.  Perhaps there needs to be special case for wlanX >> >> > devices? >> >> >> >> Yes, probably so.  But what would it be?  Factoring-in SSID is clearly >> >> not right for the usual case (i.e. one interface on a mobile device). >> >> I'm not sure what else one could use as a key. >> >> >> >> What does udev do for bridge, bond, or vlan devices?  Don't those >> >> share MAC addresses with the underlying physical device? >> >> >> >> John >> > >> > At least on ubuntu/debian the name whitelist is: >> > >> > >> > # device name whitelist >> > KERNEL!="eth*|ath*|wlan*[0-9]|msh*|ra*|sta*|ctc*|lcs*|hsi*", GOTO="persistent_net_generator_end" >> > >> > So bond or bridge don't match and don't get tampered with. >> > >> > The problem is that wlan* device names are used for both hardware and virtual >> > devices.  Udev scripts can be fixed "do the right thing" but there is not sufficient >> > information for the script to decide how to attach persistent name. >> > What values from sysfs (ie attributes) should script be using?  This probably >> > means that additional attributes needed to be added to wireless device infrastructure >> > in kernel. >> >> We could likely use the new SET_NETDEV_DEVTYPE() but I have yet to see >> where this is exported. It must be there somewhere. > > Both devices would have same type? don't see how that would help > > Imagine a system with two Atheros cards, and 2 SSID's per card. > How would devices be identified by udev to assign persistent name? Yeah sorry, I was thinking of just wlan0++ for a new wlan net device type, but yeah keeping them persistent would require more work. Luis