Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757121AbYH1AOY (ORCPT ); Wed, 27 Aug 2008 20:14:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754632AbYH1AOL (ORCPT ); Wed, 27 Aug 2008 20:14:11 -0400 Received: from rex.securecomputing.com ([203.24.151.4]:35542 "EHLO cyberguard.com.au" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753391AbYH1AOJ (ORCPT ); Wed, 27 Aug 2008 20:14:09 -0400 Message-ID: <48B5ED2C.60602@snapgear.com> Date: Thu, 28 Aug 2008 10:11:24 +1000 From: Greg Ungerer User-Agent: Thunderbird 2.0.0.16 (X11/20080723) MIME-Version: 1.0 To: Jamie Lokier CC: Bernd Petrovitsch , Parag Warudkar , Linus Torvalds , Adrian Bunk , Rusty Russell , "Alan D. Brunelle" , "Rafael J. Wysocki" , Linux Kernel Mailing List , Kernel Testers List , Andrew Morton , Arjan van de Ven , Ingo Molnar , linux-embedded@vger.kernel.org Subject: Re: [Bug #11342] Linux 2.6.27-rc3: kernel BUG at mm/vmalloc.c - bisected References: <20080826183051.GB10925@cs181140183.pp.htv.fi> <20080826205916.GB11734@cs181140183.pp.htv.fi> <1219827609.30209.29.camel@spike.firmix.at> <1219843032.30209.51.camel@spike.firmix.at> <20080827154805.GA25387@shareable.org> In-Reply-To: <20080827154805.GA25387@shareable.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2312 Lines: 56 Jamie Lokier wrote: > Bernd Petrovitsch wrote: >> If you "develop" an embedded system (which is partly system integration >> of existing apps) to be installed in the field, you don't have that many >> conceivable work loads compared to a desktop/server system. And you have >> a fixed list of drivers and applications. > > Hah! Not in my line of embedded device. > > 32MB no-MMU ARM boards which people run new things and attach new > devices to rather often - without making new hardware. Volume's too > low per individual application to get new hardware designed and made. > > I'm seriously thinking of forwarding porting the 4 year old firmware > from 2.4.26 to 2.6.current, just to get new drivers and capabilities. > Backporting is tedious, so's feeling wretchedly far from the mainline > world. > >> A usual approach is to run stress tests on several (or all) >> subsystems/services/... in parallel and if the device survives it >> functioning correctly, it is at least good enough. > > Per application. > > Some little devices run hundreds of different applications and > customers expect to customise, script themselves, and attach different > devices (over USB). The next customer in the chain expects the bits > you supplied to work in a variety of unexpected situations, even when > you advise that it probably won't do that. > > Much like desktop/server Linux, but on a small device where silly > little things like 'create a process' are a stress for the dear little > thing. > > (My biggest lesson: insist on an MMU next time!) But given you have hardware you can't change would you choose to not run Linux, even with the limitations of non-MMU? Hell no :-) Regards Greg ------------------------------------------------------------------------ Greg Ungerer -- Chief Software Dude EMAIL: gerg@snapgear.com Secure Computing Corporation PHONE: +61 7 3435 2888 825 Stanley St, FAX: +61 7 3891 3630 Woolloongabba, QLD, 4102, Australia WEB: http://www.SnapGear.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/