From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756643Ab0EaROr (ORCPT ); Mon, 31 May 2010 13:14:47 -0400 Received: from mx1.redhat.com ([209.132.183.28]:32201 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755444Ab0EaROq (ORCPT ); Mon, 31 May 2010 13:14:46 -0400 Date: Mon, 31 May 2010 20:10:07 +0300 From: "Michael S. Tsirkin" To: Avi Kivity Cc: Tom Lyon , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, chrisw@sous-sol.org, joro@8bytes.org, hjk@linutronix.de, gregkh@suse.de, aafabbri@cisco.com, scofeldm@cisco.com Subject: Re: [PATCH] VFIO driver: Non-privileged user level PCI drivers Message-ID: <20100531171007.GA6516@redhat.com> References: <4c004cba.Z/2Hpd7reetFaFC5%pugs@cisco.com> <20100530121944.GH27611@redhat.com> <4C025999.7080706@redhat.com> <20100530124949.GI27611@redhat.com> <4C0261C1.9090204@redhat.com> <20100530130332.GM27611@redhat.com> <4C026497.8070901@redhat.com> <20100530145309.GO27611@redhat.com> <4C03A285.7060902@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4C03A285.7060902@redhat.com> User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 31, 2010 at 02:50:29PM +0300, Avi Kivity wrote: > On 05/30/2010 05:53 PM, Michael S. Tsirkin wrote: >> >> So what I suggested is failing any kind of access until iommu >> is assigned. >> > > So, the kernel driver must be aware of the iommu. In which case it may > as well program it. It's a kernel driver anyway. Point is that the *device* driver is better off not programming iommu, this way we do not need to reprogram it for each device. > -- > I have a truly marvellous patch that fixes the bug which this > signature is too narrow to contain.