From owner-freebsd-stable@FreeBSD.ORG Fri Feb 10 15:18:17 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id CDB71106566B; Fri, 10 Feb 2012 15:18:17 +0000 (UTC) (envelope-from freebsd@psconsult.nl) Received: from mx1.psconsult.nl (mx1.iaf.psconsult.nl [80.89.238.138]) by mx1.freebsd.org (Postfix) with ESMTP id EB4DC8FC12; Fri, 10 Feb 2012 15:18:16 +0000 (UTC) Received: from mx1.psconsult.nl (mx1.iaf.psconsult.nl [80.89.238.138]) by mx1.psconsult.nl (8.14.4/8.14.4) with ESMTP id q1AEio77002852 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 10 Feb 2012 15:44:55 +0100 (CET) (envelope-from freebsd@psconsult.nl) Received: (from paul@localhost) by mx1.psconsult.nl (8.14.4/8.14.4/Submit) id q1AEioC5002851; Fri, 10 Feb 2012 15:44:50 +0100 (CET) (envelope-from freebsd@psconsult.nl) X-Authentication-Warning: mx1.psconsult.nl: paul set sender to freebsd@psconsult.nl using -f Date: Fri, 10 Feb 2012 15:44:50 +0100 From: Paul Schenkeveld To: freebsd-stable@freebsd.org, stable@freebsd.org Message-ID: <20120210144449.GA2358@psconsult.nl> References: <20120210145604.Horde.ewjpSpjmRSRPNSH0YRHxgAk@webmail.leidinger.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20120210145604.Horde.ewjpSpjmRSRPNSH0YRHxgAk@webmail.leidinger.net> User-Agent: Mutt/1.5.21 (2010-09-15) Cc: Subject: Re: Reducing the need to compile a custom kernel X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 10 Feb 2012 15:18:17 -0000 On Fri, Feb 10, 2012 at 02:56:04PM +0100, Alexander Leidinger wrote: > Hi, > > during some big discussions in the last monts on various lists, one of > the problems was that some people would like to use freebsd-update but > can't as they are using a custom kernel. With all the kernel modules > we provide, the need for a custom kernel should be small, but on the > other hand, we do not provide a small kernel-skeleton where you can > load just the modules you need. > > This should be easy to change. As a first step I took the generic > kernel and removed all devices which are available as modules, e.g. > the USB section consists now only of the USB_DEBUG option (so that the > module is build like with the current generic kernel). I also removed > some storage drivers which are not available as a module. The > rationale is, that I can not remove CAM from the kernel config if I > let those drivers inside (if those drivers are important enough, > someone will probably fix the problem and add the missing pieces to > generate a module). > > Such a kernel would cover situations where people compile their own > kernel because they want to get rid of some unused kernel code (and > maybe even need the memory this frees up). > > The question is, is this enough? Or asked differently, why are you > compiling a custom kernel in a production environment (so I rule out > debug options zhich are not enabled in GENERIC)? Are there options > which you add which you can not add as a module (SW_WATCHDOG comes to > my mind)? If yes, which ones and how important are they for you? - INET without INET6 - SOFTUPDATES, UFS_ACL, AUDIT, SCTP (left out for embedded devices) - Björn may add INET6 without INET - SCHED_ULE vs. SCHED_4BSD - No vga console/atkbd/psm for embedded devices - CPU_SOEKRIS, CPU_GEODE, CPU_ELAN, NO_SWAPPING for embedded devices - IPSTEALTH, IPSEC, IPSEC_FILTERTUNNEL, IPFILTER, ALTQ for firewalls - probably more I also always specify exactly one CPU type (on i386), know it made a difference in the 386/486/586 era but am not sure how much difference it makes nowadays. HTH Paul Schenkeveld