From owner-freebsd-arch@FreeBSD.ORG Tue Jan 1 02:36:23 2008 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 59A3A16A417 for ; Tue, 1 Jan 2008 02:36:23 +0000 (UTC) (envelope-from BearPerson@gmx.net) Received: from mail.gmx.net (mail.gmx.net [213.165.64.20]) by mx1.freebsd.org (Postfix) with SMTP id A60D113C447 for ; Tue, 1 Jan 2008 02:36:22 +0000 (UTC) (envelope-from BearPerson@gmx.net) Received: (qmail invoked by alias); 01 Jan 2008 02:36:21 -0000 Received: from port-83-236-56-222.dynamic.qsc.de (EHLO gmx.net) [83.236.56.222] by mail.gmx.net (mp042) with SMTP; 01 Jan 2008 03:36:21 +0100 X-Authenticated: #20254835 X-Provags-ID: V01U2FsdGVkX1/X33o1CIHXo+91lforUlsdVAYusvr6b3/azIyaLv yG01/ldY71BZBl Date: Tue, 1 Jan 2008 03:36:20 +0100 From: Karsten Behrmann To: freebsd-arch@freebsd.org Message-ID: <20080101033620.4050569c@Karsten.Behrmanns.Kasten> In-Reply-To: <4774DBB2.5060707@FreeBSD.org> References: <200712271704.44796.jhb@FreeBSD.org> <4774DBB2.5060707@FreeBSD.org> X-Mailer: Claws Mail 2.9.2 (GTK+ 2.8.18; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Y-GMX-Trusted: 0 Subject: Re: kernel features MIB X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 01 Jan 2008 02:36:23 -0000 On Fri, 28 Dec 2007 12:19:14 +0100, Kris Kennaway wrote: > John Baldwin wrote: >> One of the things we have at work is a kern.features sysctl MIB that contains >> nodes to indicate if a named feature is present. For example, on i386 we >> have kern.features.pae and we auto enable -DPAE for kernel modules if the >> currently running kernel is using PAE using that sysctl. >>[...] >> Any objections to the idea? > > I have wanted something like this for a long time. In ports land they > often need to know this kind of thing, e.g. is compat4x support enabled > in the kernel, etc. Hmm. But will everyone be running a kernel and system that the stuff they build will later run on? (when upgrading, or when building kernel and tools to be installed via NFS and pals) Mind, it could be a good heuristic for the common cases, and directly useful for some libraries, but I'm thinking that we may need some easily- accessible override knobs. I could be wrong, though. Karsten -- Open source is not about suing someone who sells your software. It is about being able to walk behind him, grinning, and waving free CDs with the equivalent of what he is trying to sell.