From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH] Enable non page boundary BAR device assignment Date: Thu, 10 Dec 2009 13:37:07 +0200 Message-ID: <20091210113707.GA12392@redhat.com> References: <1260380334-8323-1-git-send-email-agraf@suse.de> <20091210051604.GA9049@il.ibm.com> <20091210094357.GC11028@redhat.com> <20091210102301.GC10800@il.ibm.com> <6615086C-8CA1-4AFE-A95D-3DC337375749@suse.de> <20091210103737.GG10800@il.ibm.com> <20091210105655.GE11028@redhat.com> <20091210112849.GH10800@il.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Alexander Graf , kvm@vger.kernel.org To: Muli Ben-Yehuda Return-path: Received: from mx1.redhat.com ([209.132.183.28]:48820 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932118AbZLJLjs (ORCPT ); Thu, 10 Dec 2009 06:39:48 -0500 Content-Disposition: inline In-Reply-To: <20091210112849.GH10800@il.ibm.com> Sender: kvm-owner@vger.kernel.org List-ID: On Thu, Dec 10, 2009 at 01:28:49PM +0200, Muli Ben-Yehuda wrote: > On Thu, Dec 10, 2009 at 12:56:56PM +0200, Michael S. Tsirkin wrote: > > > > mmio and pio are easy, DMA you'd need an IOMMU for security, or > > > whatever uio does just for translation, > > > > uio currently does not support DMA, but I plan to fix this > > With or without an IOMMU? With an IOMMU. > > > and interrupts you probably get for free from uio. Seems eminently > > > doable to me. Why you'd want to is another matter :-) > > > > The list above ignores the biggest issue: you would have to change > > TCG code generation to make this work. > > Yep, I know nothing about TCG, only looking at this from the device > interaction side. > > > I am not sure this problem is solvable unless host and guest > > architectures are very similar. > > Now you are ignoring the most interesting issue, namely, why would you > want to solve it? What is the value of device assignment for TCG > targets? No idea. > Cheers, > Muli > -- > Muli Ben-Yehuda | muli@il.ibm.com | +972-4-8281080 > Manager, Virtualization and Systems Architecture > Master Inventor, IBM Research -- Haifa > Second Workshop on I/O Virtualization (WIOV '10): > http://sysrun.haifa.il.ibm.com/hrl/wiov2010/