From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner+w=401wt.eu-S1756298AbYE3Jw4@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1756298AbYE3Jw4 (ORCPT <rfc822;w@1wt.eu>);
	Fri, 30 May 2008 05:52:56 -0400
Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752468AbYE3Jws
	(ORCPT <rfc822;linux-kernel-outgoing>);
	Fri, 30 May 2008 05:52:48 -0400
Received: from mx2.suse.de ([195.135.220.15]:40426 "EHLO mx2.suse.de"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1751386AbYE3Jwr (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Fri, 30 May 2008 05:52:47 -0400
Date: Fri, 30 May 2008 11:52:42 +0200
Message-ID: <s5habi8ce51.wl%tiwai@suse.de>
From: Takashi Iwai <tiwai@suse.de>
To: "Yinghai Lu" <yhlu.kernel@gmail.com>
Cc: "David Miller" <davem@davemloft.net>, matthew@wil.cx,
       arjan@linux.intel.com, greg@kroah.com,
       James.Bottomley@hansenpartnership.com,
       ksummit-2008-discuss@lists.linux-foundation.org, dwmw2@infradead.org,
       linux-kernel@vger.kernel.org
Subject: Re: [Ksummit-2008-discuss] RFC: Moving firmware blobs out of the kernel.
In-Reply-To: <86802c440805291457r71340133pc413b7f1e78e5df3@mail.gmail.com>
References: <483F1232.4010003@linux.intel.com>
	<20080529204736.GZ22636@parisc-linux.org>
	<86802c440805291355p5697c775k5f0beb8163688058@mail.gmail.com>
	<20080529.143157.02330907.davem@davemloft.net>
	<86802c440805291457r71340133pc413b7f1e78e5df3@mail.gmail.com>
User-Agent: Wanderlust/2.12.0 (Your Wildest Dreams) SEMI/1.14.6 (Maruoka)
 FLIM/1.14.7 (=?ISO-8859-4?Q?Sanj=F2?=) APEL/10.6 MULE XEmacs/21.5 (beta28)
 (fuki) (x86_64-suse-linux)
MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka")
Content-Type: text/plain; charset=US-ASCII
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

At Thu, 29 May 2008 14:57:38 -0700,
Yinghai Lu wrote:
> 
> On Thu, May 29, 2008 at 2:31 PM, David Miller <davem@davemloft.net> wrote:
> > From: "Yinghai Lu" <yhlu.kernel@gmail.com>
> > Date: Thu, 29 May 2008 13:55:16 -0700
> >
> >> driver should check fw version...
> >
> > This alone is not a reason to rip the firmware out into a seperate
> > tree.  And I am absolutely not convinced that the cases where this
> > matters all universally even use firmware versions.
> >
> > I've installed the wrong ipw2200 on several occaisions.
> >
> > Furthermore, it's about distributing what works with what it's meant
> > to work with.  With this seperate scheme, I can still link in the
> > wrong firmware file (the driver doesn't check the firmware version
> > until it executes) and the driver won't work.  So this moves the
> > validation to run time, which users typically don't appreciate.
> 
> I agree. I hate to have two klibc (one for 32 bit, and one for 64bit)
> to for initramfs to load FW for qlogic...
> 
> dwmw2 's new patches to put all fw in /firmware, and built them into
> kernel could avoid that...
> 
> and could make the build process to check fw version to match with
> driver in different kernel version later...

OTOH, it doesn't give you any error at build time even if you forget
to put a firmware image beforehand.  The kernel continues to look for
a non-existing external firmware file.  In the old code, this can't
happen.

It's just a small drawback, and I still like the idea very well,
though.


Takashi