From owner-freebsd-hackers@FreeBSD.ORG Fri Jan 19 17:54:42 2007 Return-Path: X-Original-To: freebsd-hackers@freebsd.org Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 7618816A401 for ; Fri, 19 Jan 2007 17:54:42 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from harmony.bsdimp.com (vc4-2-0-87.dsl.netrack.net [199.45.160.85]) by mx1.freebsd.org (Postfix) with ESMTP id 2FED213C45A for ; Fri, 19 Jan 2007 17:54:42 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from localhost (localhost [127.0.0.1]) by harmony.bsdimp.com (8.13.4/8.13.4) with ESMTP id l0JHrxbn015845; Fri, 19 Jan 2007 10:53:59 -0700 (MST) (envelope-from imp@bsdimp.com) Date: Fri, 19 Jan 2007 10:54:20 -0700 (MST) Message-Id: <20070119.105420.387231288.imp@bsdimp.com> To: a.revolutionist@gmail.com From: "M. Warner Losh" In-Reply-To: <1169198894.6838.6.camel@aRevolutionist> References: <1169198894.6838.6.camel@aRevolutionist> X-Mailer: Mew version 4.2 on Emacs 21.3 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-2.0 (harmony.bsdimp.com [127.0.0.1]); Fri, 19 Jan 2007 10:53:59 -0700 (MST) Cc: freebsd-hackers@freebsd.org Subject: Re: Advice for Stripping the Kernel X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 19 Jan 2007 17:54:42 -0000 In message: <1169198894.6838.6.camel@aRevolutionist> aRevolutionist writes: : I am about to almost completely strip FreeBSD's kernel. The kernel shall : be stripped of sockets, drivers, memory management, and alot more. : Basically, what I shall be left with is a kernel with a few system : calls, only paging for memory management, support for only one file : system and a few other things. What advice does anyone have to give me : before I begin? Also, what section of the kernel is recommended to begin : the stripping? Many of the items that you think you need to strip can be omitted with options. One file system, for example, is easy: just compile with only UFS support. Drivers are easy too. TCP/IP can be removed as well. However, the ability to have multiple mount points is hard to strip out, and wouldn't get you much. I don't think that you can remove sockets entirely without modifications to the kernel. Stripping down the vm system would also be a challange. What are you space contraints? Warner