From owner-freebsd-net@FreeBSD.ORG Thu Nov 9 20:28:26 2006 Return-Path: X-Original-To: freebsd-net@freebsd.org Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 7AE5216A412; Thu, 9 Nov 2006 20:28:26 +0000 (UTC) (envelope-from landonf@threerings.net) Received: from smtp.earth.threerings.net (mail.threerings.net [64.127.109.101]) by mx1.FreeBSD.org (Postfix) with ESMTP id A423B43D8B; Thu, 9 Nov 2006 20:28:09 +0000 (GMT) (envelope-from landonf@threerings.net) Received: from [192.168.54.11] (timor.sea.earth.threerings.net [192.168.54.11]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by smtp.earth.threerings.net (Postfix) with ESMTP id ABB556667; Thu, 9 Nov 2006 12:28:08 -0800 (PST) In-Reply-To: <4551EA9C.5050309@FreeBSD.org> References: <4551EA9C.5050309@FreeBSD.org> Mime-Version: 1.0 (Apple Message framework v752.3) Content-Type: multipart/signed; protocol="application/pgp-signature"; micalg=pgp-sha1; boundary="Apple-Mail-26-113292544" Message-Id: <5D887638-9717-4186-86DF-1B09C7F3181F@threerings.net> Content-Transfer-Encoding: 7bit From: Landon Fuller Date: Thu, 9 Nov 2006 12:28:06 -0800 To: Bruce M. Simpson X-Pgp-Agent: GPGMail 1.1.2 (Tiger) X-Mailer: Apple Mail (2.752.3) Cc: freebsd-net@freebsd.org Subject: Re: [patch] tun(4) and tap(4) if_clone support. X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 09 Nov 2006 20:28:26 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --Apple-Mail-26-113292544 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed On Nov 8, 2006, at 06:33, Bruce M. Simpson wrote: > Landon Fuller wrote: >> Nick Barkas (snb@threerings.net) and I have added interface >> cloning support to the tun(4) and tap(4) drivers. >> >> We maintained backwards-compatible support for devfs cloning, >> which is now disabled by default -- it can be re-enabled via a >> sysctl. Interfaces that are created via devfs cloning may still be >> removed via ifconfig destroy. >> >> The latest patch is available here >> http://www.opendarwin.org/~landonf/code/patch-tuntap_ifclone >> >> I've submitted kern/105228 with the patch, and I'd be most >> appreciative of comments/suggestions. > > Interesting stuff. If it eliminates a race on creation, that has to > be a good thing; I may have run into this race in the past month or > two. It would however change tap/tun behaviour in that currently I > have a few scripts which use dd(1) to force the device node to be > created. This is undocumented behaviour specific to its devfs > implementation which perhaps I shouldn't be relying upon, before I > go on to create a bridge from several tap instances (which are then > hooked up to QEMU virtual machines). I disabled the devfs support by default with deprecation in mind, but there's no other reason it couldn't be default-enabled. What's the race you've run into? > Good work! Cheers! -landonf --Apple-Mail-26-113292544 content-type: application/pgp-signature; x-mac-type=70674453; name=PGP.sig content-description: This is a digitally signed message part content-disposition: inline; filename=PGP.sig content-transfer-encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (Darwin) iD8DBQFFU49YlplZCE/15mMRAhQKAJ9raxDQtFgBR+8PBCO+in1nbIS+ngCdFQzo 6JX6EeGNjMN1SupRLOlp7UU= =lJ6W -----END PGP SIGNATURE----- --Apple-Mail-26-113292544--