From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262993AbVALBmr (ORCPT ); Tue, 11 Jan 2005 20:42:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262994AbVALBmr (ORCPT ); Tue, 11 Jan 2005 20:42:47 -0500 Received: from mail.joq.us ([67.65.12.105]:58534 "EHLO sulphur.joq.us") by vger.kernel.org with ESMTP id S262993AbVALBmp (ORCPT ); Tue, 11 Jan 2005 20:42:45 -0500 To: Chris Wright Cc: Paul Davis , Arjan van de Ven , Lee Revell , Matt Mackall , Christoph Hellwig , Andrew Morton , mingo@elte.hu, alan@lxorguk.ukuu.org.uk, linux-kernel@vger.kernel.org Subject: Re: [PATCH] [request for inclusion] Realtime LSM References: <20050111214152.GA17943@devserv.devel.redhat.com> <200501112251.j0BMp9iZ006964@localhost.localdomain> <20050111150556.S10567@build.pdx.osdl.net> From: "Jack O'Quin" Date: Tue, 11 Jan 2005 19:43:29 -0600 In-Reply-To: <20050111150556.S10567@build.pdx.osdl.net> (Chris Wright's message of "Tue, 11 Jan 2005 15:05:56 -0800") Message-ID: <87y8ezzake.fsf@sulphur.joq.us> User-Agent: Gnus/5.1006 (Gnus v5.10.6) XEmacs/21.4 (Corporate Culture, linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Chris Wright writes: > * Paul Davis (paul@linuxaudiosystems.com) wrote: >> >On Tue, Jan 11, 2005 at 04:38:14PM -0500, Lee Revell wrote: >> >> Yes but a bug in an app running as root can trash the filesystem. The >> >> worst you can do with RT privileges is lock up the machine. >> > >> >several filesystem and IO threads run at prio -10 but not RT. >> >That makes me a bit less sure of your statement.... >> >> Its completely orthogonal. Lee didn't say "tasks running without RT >> can't mess up filesystems". He said "tasks running as root can trash >> the filesystem" and "tasks running as RT can lock up the >> machine". obviously, the intersection point (a root, RT task) is >> double trouble. > > This is straying from the core issue... But, Arjan's saying that an RT > (non-root) task could trash the filesystem if it deadlocks the machine > (because those important fs and IO threads don't run). Lexicographic ambiguity: Lee and Paul are using "trash" for things like installing a hidden suid root shell or co-opting sendmail into an open spam relay. Arjan just means crashing the system which forces reboot to run fsck. -- joq