From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: Graphics pass-through Date: Wed, 11 May 2011 16:26:54 +0300 Message-ID: <4DCA8E9E.8000705@redhat.com> References: <4D415D70.8070105@web.de> <1296175554.2891.29.camel@x201> <4DC264CD.9080700@siemens.com> <1304608642.3081.35.camel@x201> <4DC7CCB3.8030607@siemens.com> <4DC807E3.4080706@siemens.com> <1304956091.26106.39.camel@x201> <4DCA7217.5020806@redhat.com> <4DCA8A66.4080304@siemens.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Alex Williamson , Prasad Joshi , =?UTF-8?B?QW5kcsOpIFdlaWRlbWFubg==?= , "kvm@vger.kernel.org" , Oswaldo Cadenas , "Nikolaev, Maxim" To: Jan Kiszka Return-path: Received: from mx1.redhat.com ([209.132.183.28]:16163 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753229Ab1EKPiO (ORCPT ); Wed, 11 May 2011 11:38:14 -0400 In-Reply-To: <4DCA8A66.4080304@siemens.com> Sender: kvm-owner@vger.kernel.org List-ID: On 05/11/2011 04:08 PM, Jan Kiszka wrote: > On 2011-05-11 13:25, Avi Kivity wrote: > > On 05/09/2011 06:48 PM, Alex Williamson wrote: > >>> That's an interesting trace! We'll check this here, but I bet it > >>> contributes to the problems. Our FX 3800 has 1G memory... > >> > >> Yes, qemu leaves far too little MMIO space to think about assigning > >> graphics cards. Both of my cards have 512MB and I hacked qemu to leave > >> a bigger gap via something like: > >> > > > > What about 64-bit BARs? > > Aren't they backward compatible? Or do you think some guest drivers may > assume to find their 64-bit capable bars also registered as such and get > upset when seeing them as 32-bit ones? > I mean, if you have a 1GB framebuffer, put it above 4GB and hope the OS/driver can handle it. -- error compiling committee.c: too many arguments to function