From owner-freebsd-current@FreeBSD.ORG Mon Sep 15 23:05:10 2008 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 208FA1065683; Mon, 15 Sep 2008 23:05:10 +0000 (UTC) (envelope-from xcllnt@mac.com) Received: from asmtpout014.mac.com (asmtpout014.mac.com [17.148.16.89]) by mx1.freebsd.org (Postfix) with ESMTP id 09DC98FC1C; Mon, 15 Sep 2008 23:05:09 +0000 (UTC) (envelope-from xcllnt@mac.com) MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Received: from vghiya-t60.jnpr.net (natint3.juniper.net [66.129.224.36]) by asmtp014.mac.com (Sun Java(tm) System Messaging Server 6.3-7.03 (built Aug 7 2008; 32bit)) with ESMTPSA id <0K7900B82ESCNZ80@asmtp014.mac.com>; Mon, 15 Sep 2008 16:05:01 -0700 (PDT) Message-id: From: Marcel Moolenaar To: Brooks Davis In-reply-to: <20080915222155.GD24685@lor.one-eyed-alien.net> Date: Mon, 15 Sep 2008 16:05:00 -0700 References: <48CE59C2.9060307@icyb.net.ua> <200809151522.08679.jhb@freebsd.org> <3B9B5EED-6627-43F8-A5FC-7B2C7B2D38ED@mac.com> <200809151807.45844.jhb@freebsd.org> <20080915222155.GD24685@lor.one-eyed-alien.net> X-Mailer: Apple Mail (2.928.1) Cc: freebsd-current@freebsd.org, Andriy Gapon Subject: Re: sio => uart: one port is gone X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 15 Sep 2008 23:05:10 -0000 On Sep 15, 2008, at 3:21 PM, Brooks Davis wrote: > On Mon, Sep 15, 2008 at 06:07:45PM -0400, John Baldwin wrote: >> On Monday 15 September 2008 04:13:10 pm Marcel Moolenaar wrote: >>> >>> On Sep 15, 2008, at 12:22 PM, John Baldwin wrote: >>> >>>> On Monday 15 September 2008 12:55:33 pm Marcel Moolenaar wrote: >>>>> >>>>> On Sep 15, 2008, at 9:47 AM, Andriy Gapon wrote: >>>>> >>>>>> on 15/09/2008 19:41 Marcel Moolenaar said the following: >>>>>>> So, if you compile acpi(4) as a module, you must compile all >>>>>>> it's depending drivers as modules as well. Or you compile acpi >>>>>>> into the kernel... >>>>>> >>>>>> I understand the logic, but OTOH uart can work without acpi >>>>>> too, so >>>>>> it's not a strict dependency. >>>>> >>>>> Well, yes. That's what's causing your "problem". You compile a >>>>> kernel without acpi but with uart. As such, uart will be built >>>>> without acpi support. uart does indeed work without acpi. >>>>> >>>>> The problem is that people then load the acpi module at runtime >>>>> and expect uart to work with acpi. That's not going to fly. If >>>>> one builds uart as a module, all possible support is included >>>>> and it works as expected. >>>>> >>>>>> Also, this (acpi dependency) doesn't seem to be documented. >>>>> >>>>> It's standard behaviour. >>>> >>>> The problem is that right now we ship with acpi.ko as a module by >>>> default and >>>> have the loader auto-load acpi.ko IFF the machine supports ACPI. >>> >>> Well, don't do that then. Just have the device probe check if acpi >>> is >>> supported and attach if yes. >> >> It does that, the loader stuff is from someone trying to be fancy >> and save the >> memory of not having acpi.ko around if the system doesn't support >> it. This >> may in fact be dubious. :) > > While acpi.ko is a beast (about .5MB) we're really only talking > about savings > in the case when people are using GENERIC so it seems highly dubious. I tend to agree. If we didn't had the side-effects, then it's neat little thing. It would be interesting to experiment with how we can control code/data placement, so that we can bundle code or data in a way that allows us to re-use memory when the code or data is not needed (anymore). Such as kernel initialization code, driver code, firmware data, etc... -- Marcel Moolenaar xcllnt@mac.com