From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dor Laor Subject: Re: [PATCH] reserved-ram for pci-passthrough without VT-d capable hardware Date: Wed, 30 Jul 2008 17:16:06 +0300 Message-ID: <489077A6.7090105@qumranet.com> References: <1214232737-21267-1-git-send-email-benami@il.ibm.com> <20080729125312.GL11494@duo.random> <20080729131735.GM30344@one.firstfloor.org> <200807301150.44266.amit.shah@qumranet.com> <20080730135846.GB11494@duo.random> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Amit Shah , Andi Kleen , benami@il.ibm.com, Avi Kivity , Andrew Morton , kvm@vger.kernel.org, aliguori@us.ibm.com, allen.m.kay@intel.com, muli@il.ibm.com, linux-mm@kvack.org, tglx@linutronix.de, mingo@elte.hu To: Andrea Arcangeli Return-path: Received: from il.qumranet.com ([212.179.150.194]:39950 "EHLO il.qumranet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757706AbYG3ORn (ORCPT ); Wed, 30 Jul 2008 10:17:43 -0400 In-Reply-To: <20080730135846.GB11494@duo.random> Sender: kvm-owner@vger.kernel.org List-ID: Andrea Arcangeli wrote: > On Wed, Jul 30, 2008 at 11:50:43AM +0530, Amit Shah wrote: > >> * On Tuesday 29 July 2008 18:47:35 Andi Kleen wrote: >> >>>> I'm not so interested to go there right now, because while this code >>>> is useful right now because the majority of systems out there lacks >>>> VT-d/iommu, I suspect this code could be nuked in the long >>>> run when all systems will ship with that, which is why I kept it all >>>> >>> Actually at least on Intel platforms and if you exclude the lowest end >>> VT-d is shipping universally for quite some time now. If you >>> buy a Intel box today or bought it in the last year the chances are pretty >>> high that it has VT-d support. >>> >> I think you mean VT-x, which is virtualization extensions for the x86 >> architecture. VT-d is virtualization extensions for devices (IOMMU). >> > > I think Andi understood VT-d right but even if he was right that every > reader of this email that is buying a new VT-x system today is also > almost guaranteed to get a VT-d motherboard (which I disagree unless > you buy some really expensive toy), there are current large > installations of VT-x systems that lacks VT-d and that with recent > current dual/quadcore cpus are very fast and will be used for the next > couple of years and they will not upgrade just the motherboard to use > pci-passthrough. > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > In addition KVM is used in embedded too and things are slower there, we know of a specific use case (production) that demands 1:1 mapping and can't use VT-d