From owner-freebsd-current@FreeBSD.ORG Wed Aug 20 18:16:35 2014 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 08755C0A for ; Wed, 20 Aug 2014 18:16:35 +0000 (UTC) Received: from mail-pd0-x233.google.com (mail-pd0-x233.google.com [IPv6:2607:f8b0:400e:c02::233]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id D0E503534 for ; Wed, 20 Aug 2014 18:16:34 +0000 (UTC) Received: by mail-pd0-f179.google.com with SMTP id v10so12188141pde.10 for ; Wed, 20 Aug 2014 11:16:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=references:mime-version:in-reply-to:content-type :content-transfer-encoding:message-id:cc:from:subject:date:to; bh=EViyLty8mS1NilCpGRuN/5rREF2i3Pq/WXZqVYeiRNQ=; b=k8VijXtj7srJD34NiiJxzfbDJgy2bvJUuWb0SAW9AVmG1H3a67J9FkA6xzKcAVnjYE +cluSdDlXeGIvc9a2ApGDbcKw/p57ofm5n9eRrNgNB+OO6j3Ms+hXl+t0cOnt1rhyeRq zvA7ITWXsfBp7nMtLudFQZyruBO8Kdacm6CI9rt5ikLZKNLNYYi20EsQOokGFDILbeSw +BVE4Y7qCJhomqlzOmdsDS7YNYfTTSjiosPW+Lfus/61roVot3xzkv5++jJYoSLGJAKZ Gdoq9Aow1AycNc3XHlMkkffdpMYrxgwEB6pmr7gAWyKvagUzggjCLKg8NXPT9SzaoUU+ b0Fw== X-Received: by 10.67.12.175 with SMTP id er15mr30590135pad.143.1408558590171; Wed, 20 Aug 2014 11:16:30 -0700 (PDT) Received: from [10.15.207.237] (mobile-166-137-215-030.mycingular.net. [166.137.215.30]) by mx.google.com with ESMTPSA id px5sm23040018pbc.23.2014.08.20.11.16.28 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 20 Aug 2014 11:16:29 -0700 (PDT) References: <53F4E37A.6020702@mu.org> Mime-Version: 1.0 (1.0) In-Reply-To: <53F4E37A.6020702@mu.org> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Message-Id: <9D23D164-E7D1-40EB-91AE-FD5DA1F2EB65@gmail.com> X-Mailer: iPhone Mail (11D257) From: Garrett Cooper Subject: Re: RFC: Remove pty(4) Date: Wed, 20 Aug 2014 11:16:26 -0700 To: Alfred Perlstein Cc: "freebsd-current@freebsd.org" X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 20 Aug 2014 18:16:35 -0000 > On Aug 20, 2014, at 11:05, Alfred Perlstein wrote: >=20 >> On 8/20/14 11:00 AM, Davide Italiano wrote: >> One of my personal goals for 11 is to get rid of cloning mechanism >> entirely, and pty(4) is one of the few in-kernel drivers still relying >> on such mechanism. >> It's not possible, at least to my understanding, converting pty(4) to >> cdevpriv(9) as happened with other drivers. This is mainly because we >> always need a pair of devices (/dev/ptyXX and /dev/ttyXX) and >> userspace loops over ptyXX and after it successfully opens it tries to >> open the other one with the same suffix. So, having a single device is >> not really enough. >> My option, instead, is that of removing pty(4), which is nothing more >> than a compatibility driver, and move pmtx(4) code somewhere else. >> The main drawback of the removal of this is that it makes impossible >> to run FreeBSD <=3D 7 jails and SSH into them. I personally don't >> consider this a huge issue, in light of the fact that FreeBSD-7 has >> been EOL for a long time, but I would like to hear other people >> comments. >>=20 >> The code review for the proposed change can be found here: >> https://reviews.freebsd.org/D659 >>=20 >> If I won't get any objection I'll commit this in one week time, i.e. >> August 27th. > I don't think that we want to break userland apps pre-7.x. Do you mean ju= st jails are broken? Or is all pre-7.x compat? I believe either is dicey. = What is the reason for getting rid of cloning? What is the difficulty in ma= intaining the old interface? Doing this would also break login shells, xterms, etc, right? Some compa= nies I worked for built their appliance products on newer OSes, and they wer= e based off of 6 and 7. This seems like something that deserves being tossed= into the compat layer if it's something that can be converted over to the n= ew interface. Thanks! -Garrett=