From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754737Ab2AXA0i (ORCPT ); Mon, 23 Jan 2012 19:26:38 -0500 Received: from zeniv.linux.org.uk ([195.92.253.2]:39493 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754664Ab2AXA0e (ORCPT ); Mon, 23 Jan 2012 19:26:34 -0500 Date: Tue, 24 Jan 2012 00:26:20 +0000 From: Al Viro To: Linus Torvalds Cc: Serge Hallyn , Dave Hansen , sukadev@linux.vnet.ibm.com, Andy Whitcroft , Matt Helsley , linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org Subject: Re: [RFC] fix devpts mount behavior Message-ID: <20120124002620.GI23916@ZenIV.linux.org.uk> References: <20120124000517.GA28878@sergelap> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 23, 2012 at 04:13:49PM -0800, Linus Torvalds wrote: > On Mon, Jan 23, 2012 at 4:05 PM, Serge Hallyn > wrote: > > > > I've been playing for the last week with ways to fix this, and in the > > end I can see two ways. > > How about a third way: > > - make "newinstance" mandatory (and "-o newinstance" is a no-op) and > forget about the whole issue. > > - if you really want to remount the old global one, you have to use a > bind mount of that original mount instead. > > There may be some subtle reason why the above is totally broken and > just fundamnetally wouldn't work, and breaks all existing setups, but > maybe it's worth at least discussing as an option? Hell knows... That's certainly what I would have prefered, but I wonder about existing practices along the lines of "mount it in chroot jail from inside that jail" (as opposed to mount --bind /dev/pts /jail/dev/pts while preparing it). Posted patch is too ugly to live and as for the new kind of namespace... yuck. We already have far too many :-/