From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BCEF6C46464 for ; Mon, 13 Aug 2018 16:36:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6C8C621564 for ; Mon, 13 Aug 2018 16:36:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6C8C621564 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lxorguk.ukuu.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730129AbeHMTTV (ORCPT ); Mon, 13 Aug 2018 15:19:21 -0400 Received: from www.llwyncelyn.cymru ([82.70.14.225]:53798 "EHLO fuzix.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728293AbeHMTTV (ORCPT ); Mon, 13 Aug 2018 15:19:21 -0400 Received: from alans-desktop (82-70-14-226.dsl.in-addr.zen.co.uk [82.70.14.226]) by fuzix.org (8.15.2/8.15.2) with ESMTP id w7DGZ3em015022; Mon, 13 Aug 2018 17:35:03 +0100 Date: Mon, 13 Aug 2018 17:35:02 +0100 From: Alan Cox To: Andy Lutomirski Cc: "Theodore Y. Ts'o" , David Howells , "Eric W. Biederman" , Al Viro , John Johansen , Tejun Heo , SELinux-NSA , Paul Moore , Li Zefan , Linux API , apparmor@lists.ubuntu.com, Casey Schaufler , Fenghua Yu , Greg Kroah-Hartman , Eric Biggers , LSM List , Tetsuo Handa , Johannes Weiner , Stephen Smalley , tomoyo-dev-en@lists.sourceforge.jp, "open list:CONTROL GROUP (CGROUP)" , Linus Torvalds , Linux FS Devel , LKML , Miklos Szeredi Subject: Re: BUG: Mount ignores mount options Message-ID: <20180813173502.1a7a1d9c@alans-desktop> In-Reply-To: References: <20180810153902.GH21087@thunk.org> <87d0uqpba5.fsf@xmission.com> <153313703562.13253.5766498657900728120.stgit@warthog.procyon.org.uk> <22361.1533913891@warthog.procyon.org.uk> <28045.1533916438@warthog.procyon.org.uk> <20180810161400.GA627@thunk.org> Organization: Intel Corporation X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > If the same block device is visible, with rw access, in two different > containers, I don't see any anything good can happen. Sure, with the At the raw level there are lots of use cases involving high performance data capture, media streaming and the like. At the file system layer you can use GFS2 for example. So there are cases where it's possible. There are even cases where it's actually useful at the filesystem level although not many I agree. Alan