Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750965AbWA2NJe (ORCPT ); Sun, 29 Jan 2006 08:09:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750963AbWA2NJe (ORCPT ); Sun, 29 Jan 2006 08:09:34 -0500 Received: from pentafluge.infradead.org ([213.146.154.40]:10396 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S1750962AbWA2NJd (ORCPT ); Sun, 29 Jan 2006 08:09:33 -0500 Subject: Re: [Keyrings] Re: [PATCH 01/04] Add multi-precision-integer maths library From: Arjan van de Ven To: Adrian Bunk Cc: Trond Myklebust , Christoph Hellwig , keyrings@linux-nfs.org, linux-kernel@vger.kernel.org In-Reply-To: <20060129122901.GX3777@stusta.de> References: <1138312694656@2gen.com> <1138312695665@2gen.com> <6403.1138392470@warthog.cambridge.redhat.com> <20060127204158.GA4754@hardeman.nu> <20060128002241.GD3777@stusta.de> <20060128104611.GA4348@hardeman.nu> <1138466271.8770.77.camel@lade.trondhjem.org> <20060128165732.GA8633@hardeman.nu> <1138504829.8770.125.camel@lade.trondhjem.org> <20060129113320.GA21386@hardeman.nu> <20060129122901.GX3777@stusta.de> Content-Type: text/plain Date: Sun, 29 Jan 2006 14:09:08 +0100 Message-Id: <1138540148.3002.9.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1165 Lines: 34 > > You are taking the wrong approach. > > The _only_ question that matters is: > Why is it technically impossible to do the same in userspace? > > If it's technically possible to do the same in userspace, it must not be > done in the kernel. that is not a reasonable statement because... 1) you can do all of tcp/ip in userspace just fine 2) you can do the NFS server in userspace 3) ... 4) ... there are reasons why things that can be done in userspace sometimes still make sense to do in kernel space, performance could be one of those reasons, being unreasonably complex in userspace is another. Identity management to some degree belongs in the kernel, simply because identity *enforcing* is in the kernel. Some things related to security need to be in the kernel at least partially just to avoid a LOT of hairy issues and never ending series of security holes due to the exceptional complexity you get. - 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/