Return-path: Received: from smtp.rutgers.edu ([128.6.72.243]:29751 "EHLO annwn13.rutgers.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756690AbXFPWRt (ORCPT ); Sat, 16 Jun 2007 18:17:49 -0400 From: Michael Wu To: Johannes Berg Subject: Re: [Take 2] mac80211 IEEE802.11e/WMM code cleanup Date: Sat, 16 Jun 2007 15:16:11 -0700 Cc: Zhu Yi , linux-wireless@vger.kernel.org, "John W. Linville" , David Lamparter References: <20070611085950.GA5540@mail.intel.com> <200706161129.13782.flamingice@sourmilk.net> <1182019869.9058.57.camel@johannes.berg> In-Reply-To: <1182019869.9058.57.camel@johannes.berg> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart4179980.ZIoWvcF0Am"; protocol="application/pgp-signature"; micalg=pgp-sha1 Message-Id: <200706161516.16447.flamingice@sourmilk.net> Sender: linux-wireless-owner@vger.kernel.org List-ID: --nextPart4179980.ZIoWvcF0Am Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline On Saturday 16 June 2007 11:51, Johannes Berg wrote: > On Sat, 2007-06-16 at 11:29 -0700, Michael Wu wrote: > > I think that decision was made without much consideration to the > > implementation details. > > I don't think the implementation details are much of a problem. It's > just a bit of message bouncing which is trivial. Except of course when > you consider wext, but hey, no need to consider that for this discussion > since you're proposing ditching wext completely. Not that I don't want > to ditch it, but people still use it and probably will. Heck, people > still use 'ifconfig'... > I'm not proposing to ditch wext completely. When did I say that? > > I thought it was a good idea then, but passing > > messages from userspace to the kernel and then to userspace again is > > really a waste of time. > > It's not happening a lot so it's not a waste of *much* time ;) > It's a waste of time when nl80211 needs to be patched every time we want an= =20 additional command in the userspace MLME. > > NetworkManager already uses wpa_supplicant to avoid all the > > nasty details of dealing with wireless configuration, so why not keep > > using it for everything instead of hiding wpa_supplicant behind nl80211? > > I hope that nm would start using nl80211 instead of talking to > wpa_supplicant and just start wpa_supplicant if necessary. Or maybe some > startup scripts start the userspace MLME (wpa_supplicant) for the > interfaces during boot/hotplug. > I don't think switching NM to nl80211 is reasonable unless you find someone= to=20 port all the legacy drivers to cfg80211 too.=20 > > This is > > more simple and direct and allows the kernel to expose exactly what the > > hardware/kernel can do. Userspace won't have to change much and nl80211 > > won't have to support every possible thing a userspace MLME would want. > > It's not that the kernel will have to support everything that a > userspace MLME would want, but rather that the kernel needs to support > everything the MLME would want, to support fullmac drivers. > I don't think the needs of a firmware based MLME are necessarily the same a= s a=20 userspace MLME. Some commands will certainly be the same, but just because= =20 the commands are there doesn't mean it's good to make them work if you have= =20 to fake it. The kernel should show what the hardware/stack can do and nothi= ng=20 more. > Another counter: when you have a tool like 'iw' that David wrote, then > it'll need to look for the userspace MLME every time you invoke it and > start communicating with it instead of the kernel. That's likely a waste > of much more time than just bouncing the messages. > I think the difference is trivial. Using nl80211 for what is effectively IP= C=20 seems very incorrect to me. =2DMichael Wu --nextPart4179980.ZIoWvcF0Am Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) iD8DBQBGdGEwT3Oqt9AH4aERArdeAKC9IzUC0WnInF7SJ5LcVCzHyKG9PgCcCLQV wAcIsddOpIhBr4On1ELB89Q= =aY3v -----END PGP SIGNATURE----- --nextPart4179980.ZIoWvcF0Am-- -: To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org: More majordomo info at http: //vger.kernel.org/majordomo-info.html