From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [Qemu-devel] Re: [RFC PATCH 4/7] ide: IOMMU support Date: Thu, 15 Jul 2010 20:22:31 +0300 Message-ID: <4C3F43D7.1040301@redhat.com> References: <1279086307-9596-1-git-send-email-eduard.munteanu@linux360.ro> <4C3E2C2E.70507@codemonkey.ws> <20100714222401.GB21126@sequoia.sous-sol.org> <201007151128.27487.paul@codesourcery.com> <20100715165214.GV14017@sequoia.sous-sol.org> <4C3F3F0D.1000103@redhat.com> <20100715171710.GZ14017@sequoia.sous-sol.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Paul Brook , Anthony Liguori , Joerg Roedel , Eduard - Gabriel Munteanu , qemu-devel@nongnu.org, kvm@vger.kernel.org To: Chris Wright Return-path: Received: from mx1.redhat.com ([209.132.183.28]:8107 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933860Ab0GORWy (ORCPT ); Thu, 15 Jul 2010 13:22:54 -0400 In-Reply-To: <20100715171710.GZ14017@sequoia.sous-sol.org> Sender: kvm-owner@vger.kernel.org List-ID: On 07/15/2010 08:17 PM, Chris Wright wrote: > >> For emulated device, it seems like we can ignore ATS completely, no? >> > Not if you want to emulate an ATS capable device ;) > What I meant was that the whole request translation, invalidate, dma using a translated address thing is invisible to software. We can emulate an ATS capable device by going through the iommu every time. -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.