Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754954AbYFETRc (ORCPT ); Thu, 5 Jun 2008 15:17:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753129AbYFETRF (ORCPT ); Thu, 5 Jun 2008 15:17:05 -0400 Received: from e31.co.us.ibm.com ([32.97.110.149]:36258 "EHLO e31.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752197AbYFETRD (ORCPT ); Thu, 5 Jun 2008 15:17:03 -0400 Date: Thu, 5 Jun 2008 14:16:47 -0500 From: "Serge E. Hallyn" To: "Serge E. Hallyn" Cc: Pavel Emelyanov , Andrew Morton , Linux Kernel Mailing List Subject: Re: [PATCH 2/2] devscgroup: make white list more compact in some cases Message-ID: <20080605191647.GA27304@us.ibm.com> References: <4847A7BE.5010603@openvz.org> <20080605142338.GB11919@us.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080605142338.GB11919@us.ibm.com> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1415 Lines: 42 Quoting Serge E. Hallyn (serue@us.ibm.com): > Quoting Pavel Emelyanov (xemul@openvz.org): > > Consider you added a 'c foo:bar r' permission to some cgroup and then > > (a bit later) 'c'foo:bar w' for it. After this you'll see a > > c foo:bar r > > c foo:bar w > > lines in a devices.list file. > > > > Another example - consider you added 10 'c foo:bar r' permissions to > > some cgroup (e.g. by mistake). After this you'll see 10 > > c foo:bar r > > lines in a list file. > > > > This is weird. This situation also has one more annoying consequence. > > Having many items in a white list makes permissions checking slower, > > sine it has to walk a longer list. > > > > The proposal is to merge permissions for items, that correspond to the > > same device. > > > > Signed-off-by: Pavel Emelyanov > > Acked-by: Serge Hallyn > > Thanks. I suppose if it was deemed worth it, the other thing you could > do would be to detect when you have a rule > > c foo:bar r > > and you add a rule > > c foo:(all) r But a private email response preferred the each-entry-is-separate semantics, so I retract that suggestion. -serge -- 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/