From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH] kvm-userspace: set pci mem to start at 0xc100000 and vesa to 0xc000000 Date: Sun, 18 Jan 2009 10:41:36 +0200 Message-ID: <4972EB40.4040306@redhat.com> References: <1231637150-12127-1-git-send-email-ieidus@redhat.com> <1231637150-12127-2-git-send-email-ieidus@redhat.com> <20090117005748.GA32499@sequoia.sous-sol.org> <49713302.1010705@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Chris Wright , kvm@vger.kernel.org To: Izik Eidus Return-path: Received: from mx2.redhat.com ([66.187.237.31]:43703 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1763014AbZARIlv (ORCPT ); Sun, 18 Jan 2009 03:41:51 -0500 In-Reply-To: <49713302.1010705@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: Izik Eidus wrote: >> b) It is brute force. I'm not sure it really matters all that much to >> limit a 32-bit (non-PAE) guest to 3G, but it's a little extreme for the >> cases that don't care about the large hole. >> Is there anyway to make it dynamic based on the requirements of the >> devices that are part of the launched VM? >> > > There is (you need to transfer data to the bios but it is > possible...), the thing is - there was concern that > it will make windows crazy if you keep changing the devices physical > mapping > > Avi what do you think? It's possible for the bios to size the resources needed by PCI devices (excluding hotplug) and tell qemu where to map RAM. However I don't think that's what standard bioses do. On a barcelona I have here the hole is 0.75GB; I think either 0.5 or 1 GB holes are reasonable. I prefer 1GB so we can accommodate large assigned framebuffers; I don't see people running 4GB Windows guests (and Linux guests can use PAE). -- error compiling committee.c: too many arguments to function