Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763666AbYCFB6J (ORCPT ); Wed, 5 Mar 2008 20:58:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759115AbYCFB5x (ORCPT ); Wed, 5 Mar 2008 20:57:53 -0500 Received: from pentafluge.infradead.org ([213.146.154.40]:41784 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757592AbYCFB5x (ORCPT ); Wed, 5 Mar 2008 20:57:53 -0500 Date: Wed, 5 Mar 2008 17:55:13 -0800 From: Greg KH To: Pavel Emelyanov Cc: Andrew Morton , Linux Kernel Mailing List , Paul Menage , Sukadev Bhattiprolu , Serge Hallyn Subject: Re: [PATCH 0/9] Devices accessibility control group (v4) Message-ID: <20080306015513.GA5359@kroah.com> References: <47CED717.60406@openvz.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <47CED717.60406@openvz.org> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1466 Lines: 44 On Wed, Mar 05, 2008 at 08:23:35PM +0300, Pavel Emelyanov wrote: > Changes from v3: > * Ported on 2.6.25-rc3-mm1; > * Re-splitted into smaller pieces; > * Added more comments to tricky places. > > This controller allows to tune the devices accessibility by tasks, > i.e. grant full access for /dev/null, /dev/zero etc, grant read-only > access to IDE devices and completely hide SCSI disks. From within the kernel itself? The kernel should not be keeping track of the mode of devices, that's what the filesystem holding /dev is for. Those modes change all the time depending on the device plugged in, and the user using the "console". Why should the kernel need to worry about any of this? > Tasks still can call mknod to create device files, regardless of > whether the particular device is visible or accessible, but they > may not be able to open it later. > > This one hides under CONFIG_CGROUP_DEVS option. > > To play with it - run a standard procedure: > > # mount -t container none /cont/devs -o devices > # mkdir /cont/devs/0 > # echo -n $$ > /cont/devs/0/tasks What is /cont/ for? > and tune device permissions. How is this done? Why would the kernel care about this stuff? confused, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/