From mboxrd@z Thu Jan 1 00:00:00 1970 From: Muli Ben-Yehuda Subject: Re: [PATCH] Enable non page boundary BAR device assignment Date: Thu, 10 Dec 2009 13:28:49 +0200 Message-ID: <20091210112849.GH10800@il.ibm.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> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Alexander Graf , kvm@vger.kernel.org To: "Michael S. Tsirkin" Return-path: Received: from mtagate3.uk.ibm.com ([194.196.100.163]:44749 "EHLO mtagate3.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933959AbZLJL2o (ORCPT ); Thu, 10 Dec 2009 06:28:44 -0500 Received: from d06nrmr1806.portsmouth.uk.ibm.com (d06nrmr1806.portsmouth.uk.ibm.com [9.149.39.193]) by mtagate3.uk.ibm.com (8.13.1/8.13.1) with ESMTP id nBABSoNs006740 for ; Thu, 10 Dec 2009 11:28:50 GMT Received: from d06av01.portsmouth.uk.ibm.com (d06av01.portsmouth.uk.ibm.com [9.149.37.212]) by d06nrmr1806.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id nBABSoZE1122354 for ; Thu, 10 Dec 2009 11:28:50 GMT Received: from d06av01.portsmouth.uk.ibm.com (loopback [127.0.0.1]) by d06av01.portsmouth.uk.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id nBABSncZ006449 for ; Thu, 10 Dec 2009 11:28:50 GMT Content-Disposition: inline In-Reply-To: <20091210105655.GE11028@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: 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? > > 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? 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/