Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755412AbYKIOe4 (ORCPT ); Sun, 9 Nov 2008 09:34:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754800AbYKIOep (ORCPT ); Sun, 9 Nov 2008 09:34:45 -0500 Received: from mx1.suse.de ([195.135.220.2]:48303 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754765AbYKIOeo (ORCPT ); Sun, 9 Nov 2008 09:34:44 -0500 Cc: Greg KH , "Zhao, Yu" , "linux-pci@vger.kernel.org" , "achiang@hp.com" , "grundler@parisc-linux.org" , "mingo@elte.hu" , "jbarnes@virtuousgeek.org" , "matthew@wil.cx" , "randy.dunlap@oracle.com" , "rdreier@cisco.com" , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" , "virtualization@lists.linux-foundation.org" Message-Id: From: Alexander Graf To: Pavel Machek In-Reply-To: <20081109141909.GA2458@ucw.cz> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (Apple Message framework v929.2) Subject: Re: [PATCH 16/16 v6] PCI: document the new PCI boot parameters Date: Sun, 9 Nov 2008 15:34:33 +0100 References: <20081022083809.GA3757@yzhao12-linux.sh.intel.com> <20081022084531.GP3773@yzhao12-linux.sh.intel.com> <20081106043235.GA30292@kroah.com> <4913AA03.5060807@intel.com> <20081107025032.GA12824@kroah.com> <4913B8A5.5010806@intel.com> <20081107061603.GC3860@kroah.com> <20081109141909.GA2458@ucw.cz> X-Mailer: Apple Mail (2.929.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1976 Lines: 50 >>>>> If we do resource rebalance after system is up, do you think >>>>> there is any >>>>> side effect or impact to other subsystem other than PCI (e.g. >>>>> MTRR)? >>>> I don't think so. >>>>> I haven't had much thinking on the dynamical resource rebalance. >>>>> If you >>>>> have any idea about this, can you please suggest? >>>> Yeah, it's going to be hard :) >>>> We've thought about this in the past, and even Microsoft said it >>>> was >>>> going to happen for Vista, but they realized in the end, like we >>>> did a >>>> few years previously, that it would require full support of all PCI >>>> drivers as well (if you rebalance stuff that is already bound to a >>>> driver.) So they dropped it. >>>> When would you want to do this kind of rebalancing? Before any PCI >>>> driver is bound to any devices? Or afterwards? >>> >>> I guess if we want the rebalance dynamic, then we should have it >>> full -- >>> the rebalance would be functional even after the driver is loaded. >>> >>> But in most cases, there will be problem when we unload driver >>> from a hard >>> disk controller, etc. We can mount root on a ramdisk and do the >>> rebalance >>> there, but it's complicated for a real user. >>> >>> So looks like doing rebalancing before any driver is bound to any >>> device is >>> also a nice idea, if user can get a shell to do rebalance before >>> built-in >>> PCI driver grabs device. >> >> That's not going to work, it needs to happen before any PCI device is >> bound, which is before init runs. > > We could run shell from early initrd... And PCI is not required for > initrd, right? You can't be sure of that - compile your ATA driver =y and you'll definitely end up using PCI. Alex -- 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/