From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763636AbXK2RlS (ORCPT ); Thu, 29 Nov 2007 12:41:18 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759693AbXK2RlL (ORCPT ); Thu, 29 Nov 2007 12:41:11 -0500 Received: from [81.2.110.250] ([81.2.110.250]:38998 "EHLO the-village.bc.nu" rhost-flags-FAIL-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1758938AbXK2RlK (ORCPT ); Thu, 29 Nov 2007 12:41:10 -0500 Date: Thu, 29 Nov 2007 17:36:01 +0000 From: Alan Cox To: tvrtko.ursulin@sophos.com Cc: Al Viro , Casey Schaufler , Christoph Hellwig , linux-kernel@vger.kernel.org, Valdis.Kletnieks@vt.edu Subject: Re: Out of tree module using LSM Message-ID: <20071129173601.34273083@the-village.bc.nu> In-Reply-To: References: <20071128183040.GW8181@ftp.linux.org.uk> X-Mailer: Claws Mail 2.10.0 (GTK+ 2.10.14; i386-redhat-linux-gnu) Organization: Red Hat UK Cyf., Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, Y Deyrnas Gyfunol. Cofrestrwyd yng Nghymru a Lloegr o'r rhif cofrestru 3798903 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > closed. But more importantly further access to it can be blocked until > appropriate actions are taken which also applies with your example, no? Is That bit is hard- very hard. > it possible to open for execute and have dirty mappings (or open for > write) on a file at the same time? If I want I can have 16 threads executing code in a shared object being written to by ten other programs at once and shared over a network while we are at it. Its probably not a good idea but I can do it if I have reason to. Unix and Linux likewise take the basic view that locking is a problem for the user, while file permissions prevent it being made a problem for other users.