From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from xc.sipsolutions.net ([83.246.72.84]:51941 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756964AbZDGNOE (ORCPT ); Tue, 7 Apr 2009 09:14:04 -0400 Subject: Re: attempt to scan fails (device busy) if essid/ssid was changed recently From: Johannes Berg To: Maxim Levitsky Cc: linux-wireless , linux-kernel In-Reply-To: <1239109497.15015.12.camel@maxim-laptop> (sfid-20090407_150534_375314_4DA28551) References: <1239062401.4705.23.camel@maxim-laptop> (sfid-20090407_020013_939126_90578556) <1239092296.22453.1.camel@johannes.local> <1239108689.15015.3.camel@maxim-laptop> (sfid-20090407_145137_740898_8D0C40FD) <1239109001.22453.40.camel@johannes.local> <1239109497.15015.12.camel@maxim-laptop> (sfid-20090407_150534_375314_4DA28551) Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-M74qu0Gb2BZ7cPztZp/z" Date: Tue, 07 Apr 2009 15:13:30 +0200 Message-Id: <1239110010.22453.41.camel@johannes.local> (sfid-20090407_151426_264016_DE682477) Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: --=-M74qu0Gb2BZ7cPztZp/z Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Tue, 2009-04-07 at 16:04 +0300, Maxim Levitsky wrote: > > > > > Looking a bit deeper I discovered that each time NM disconnects f= rom a > > > > > networks it sets random ssid/essid to the card (using wireless > > > > > extensions) > > > >=20 > > > > This forces a scan > > > >=20 > > > > > After that scan fails for some time. > > > > >=20 > > > > > as a NM free example you can run=20 > > > > >=20 > > > > > iwconfig wlan0 essid dummy > > > > > iwlist scan > > > >=20 > > > > 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)? > >=20 > > Nothing. Wext sucks, news at 11, yadda. > Thanks. > Everything understood. Of course, we can go back to dropping the scan request, but that wouldn't be very nice. Is this creating any problems? johannes --=-M74qu0Gb2BZ7cPztZp/z Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Comment: Johannes Berg (powerbook) iQIcBAABAgAGBQJJ21F4AAoJEKVg1VMiehFYBPQQAIwMkG6bhZm4TxYnAC7UBT2+ gmGmcjU7ewhnlAuJjeKAjsznvD/KovTV8fY3J+EzKAE0TJ4ix8CaUFpZvSF74ZRc MBw/XoothpoxoqmI4q+H/huNVoVHRY/c7xMzgP7EXUElB0qOJGrMelO2eJS0l0uz HE5uHkqhsbDAE44QVfRZTADGj3B8eXseuSWKnqLE7nQsiMJMh7O4L+nFBaVIJ7dL CdTmFoDvAMjPKNeK+tMeSDDiaF+8oRjhvwhcVaj5VDyNQKJa8ekzXubA7lAespF+ /SdsxqUdrIPBGZk6694ls6/HJ/bzJGuVwtlmyJz+EShAH9yLIDEAxjnz0bUumIPJ 3odR4kIMvSLQh2r0VCX/8jlhcIDGeYEni1oBWUatO85I9h708G3zhsHP3V/bfGoU 3GbUy++jpvNvNjgUvW2kVM+5j4jVhTqRFfnELJBxRqvEIDvU7hIHElrpIr98DaI4 yvkgqSeUkRdyU95rmWWC04dk5e3UnsHsUFmeSCUubaGJ+lqcKIxgnT7tDHYtquhn ns2mlVa7jJunLWReZall8kF53ilh0wAlDNt32pUY3lNMkume4X5V6wFslVv/3dPI 9ysir9brQ4LAPwtaz8a+mAFTZPdxoDK2X3j3z7lVqb78R3G+Q7HaiXB/4Fs2rbwp gn+ohGiveTg42UzDUZ+Y =dXuV -----END PGP SIGNATURE----- --=-M74qu0Gb2BZ7cPztZp/z--