From mboxrd@z Thu Jan 1 00:00:00 1970 From: Muli Ben-Yehuda Subject: Re: [PATCH] KVM: PCIPT: VT-d support Date: Thu, 10 Jul 2008 19:00:47 +0300 Message-ID: <20080710160047.GE7273@il.ibm.com> References: <1215681282-3449-1-git-send-email-benami@il.ibm.com> <200807101730.26586.sheng.yang@intel.com> <1215683513.31546.175.camel@cluwyn.haifa.ibm.com> <200807101807.28719.sheng.yang@intel.com> <20080710144124.GD7273@il.ibm.com> <48762374.3000002@qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "Yang, Sheng" , Ben-Ami Yassour1 , kvm@vger.kernel.org, amit.shah@qumranet.com, weidong.han@intel.com, anthony@codemonkey.ws, "Kay, Allen M" To: Avi Kivity Return-path: Received: from mtagate5.de.ibm.com ([195.212.29.154]:34946 "EHLO mtagate5.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750773AbYGJQBT (ORCPT ); Thu, 10 Jul 2008 12:01:19 -0400 Received: from d12nrmr1607.megacenter.de.ibm.com (d12nrmr1607.megacenter.de.ibm.com [9.149.167.49]) by mtagate5.de.ibm.com (8.13.8/8.13.8) with ESMTP id m6AG1IZY451632 for ; Thu, 10 Jul 2008 16:01:18 GMT Received: from d12av03.megacenter.de.ibm.com (d12av03.megacenter.de.ibm.com [9.149.165.213]) by d12nrmr1607.megacenter.de.ibm.com (8.13.8/8.13.8/NCO v9.0) with ESMTP id m6AG1HuT3694804 for ; Thu, 10 Jul 2008 18:01:17 +0200 Received: from d12av03.megacenter.de.ibm.com (loopback [127.0.0.1]) by d12av03.megacenter.de.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id m6AG1HZR011380 for ; Thu, 10 Jul 2008 18:01:17 +0200 Content-Disposition: inline In-Reply-To: <48762374.3000002@qumranet.com> Sender: kvm-owner@vger.kernel.org List-ID: On Thu, Jul 10, 2008 at 05:57:56PM +0300, Avi Kivity wrote: > It makes sense to initialize VT-d before. Since memslots can be > created and destroyed dynamically, with the current implementation > we can see > > create slot > create slot > init VT-d > create slot > > which means we need to support both slot-creation-after-VT-d and > init-VT-d-after-slot-creation. If we initialize VT-d up front, we > only need to support (and test) one scenario. Fair enough---we'll take a look at whether initializing VT-d first introduces any complications other than hot-plug (see below). > On the other hand, this means that you will not be able to assign > devices unless you specified this when creating the VM; but I think > this is fair. It will be nice to support hot-plugged pass-through devices some time in the future. Cheers, Muli