From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751167AbbKJGUN (ORCPT ); Tue, 10 Nov 2015 01:20:13 -0500 Received: from gate.crashing.org ([63.228.1.57]:50436 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750879AbbKJGUK (ORCPT ); Tue, 10 Nov 2015 01:20:10 -0500 Message-ID: <1447133190.31884.65.camel@kernel.crashing.org> Subject: Re: [PATCH v4 0/6] virtio core DMA API conversion From: Benjamin Herrenschmidt To: Andy Lutomirski Cc: Andy Lutomirski , David Woodhouse , "linux-kernel@vger.kernel.org" , "David S. Miller" , sparclinux@vger.kernel.org, Joerg Roedel , Christian Borntraeger , Cornelia Huck , Sebastian Ott , Paolo Bonzini , Christoph Hellwig , KVM , Martin Schwidefsky , linux-s390 , Linux Virtualization , "Michael S. Tsirkin" Date: Tue, 10 Nov 2015 16:26:30 +1100 In-Reply-To: References: <20151109133624-mutt-send-email-mst@redhat.com> <1447109937.31884.42.camel@kernel.crashing.org> <1447121076.31884.61.camel@kernel.crashing.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.18.1 (3.18.1-1.fc23) Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2015-11-09 at 18:18 -0800, Andy Lutomirski wrote: > > Which leaves the special case of Xen, where even preexisting devices > don't bypass the IOMMU.  Can we keep this specific to powerpc and > sparc?  On x86, this problem is basically nonexistent, since the IOMMU > is properly self-describing. > > IOW, I think that on x86 we should assume that all virtio devices > honor the IOMMU. You don't like performances ? :-) Cheers, Ben. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: [PATCH v4 0/6] virtio core DMA API conversion Date: Tue, 10 Nov 2015 16:26:30 +1100 Message-ID: <1447133190.31884.65.camel@kernel.crashing.org> References: <20151109133624-mutt-send-email-mst@redhat.com> <1447109937.31884.42.camel@kernel.crashing.org> <1447121076.31884.61.camel@kernel.crashing.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org List-Archive: List-Post: To: Andy Lutomirski Cc: Joerg Roedel , KVM , linux-s390 , "Michael S. Tsirkin" , Sebastian Ott , "linux-kernel@vger.kernel.org" , Christoph Hellwig , Christian Borntraeger , Andy Lutomirski , sparclinux@vger.kernel.org, Paolo Bonzini , Linux Virtualization , David Woodhouse , "David S. Miller" , Martin Schwidefsky List-ID: T24gTW9uLCAyMDE1LTExLTA5IGF0IDE4OjE4IC0wODAwLCBBbmR5IEx1dG9taXJza2kgd3JvdGU6 Cj4gCj4gV2hpY2ggbGVhdmVzIHRoZSBzcGVjaWFsIGNhc2Ugb2YgWGVuLCB3aGVyZSBldmVuIHBy ZWV4aXN0aW5nIGRldmljZXMKPiBkb24ndCBieXBhc3MgdGhlIElPTU1VLsKgIENhbiB3ZSBrZWVw IHRoaXMgc3BlY2lmaWMgdG8gcG93ZXJwYyBhbmQKPiBzcGFyYz/CoCBPbiB4ODYsIHRoaXMgcHJv YmxlbSBpcyBiYXNpY2FsbHkgbm9uZXhpc3RlbnQsIHNpbmNlIHRoZSBJT01NVQo+IGlzIHByb3Bl cmx5IHNlbGYtZGVzY3JpYmluZy4KPiAKPiBJT1csIEkgdGhpbmsgdGhhdCBvbiB4ODYgd2Ugc2hv dWxkIGFzc3VtZSB0aGF0IGFsbCB2aXJ0aW8gZGV2aWNlcwo+IGhvbm9yIHRoZSBJT01NVS4KCllv dSBkb24ndCBsaWtlIHBlcmZvcm1hbmNlcyA/IDotKQoKQ2hlZXJzLApCZW4uCl9fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fClZpcnR1YWxpemF0aW9uIG1haWxp bmcgbGlzdApWaXJ0dWFsaXphdGlvbkBsaXN0cy5saW51eC1mb3VuZGF0aW9uLm9yZwpodHRwczov L2xpc3RzLmxpbnV4Zm91bmRhdGlvbi5vcmcvbWFpbG1hbi9saXN0aW5mby92aXJ0dWFsaXphdGlv bg== From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Date: Tue, 10 Nov 2015 05:26:30 +0000 Subject: Re: [PATCH v4 0/6] virtio core DMA API conversion Message-Id: <1447133190.31884.65.camel@kernel.crashing.org> List-Id: References: <20151109133624-mutt-send-email-mst@redhat.com> <1447109937.31884.42.camel@kernel.crashing.org> <1447121076.31884.61.camel@kernel.crashing.org> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit To: Andy Lutomirski Cc: Joerg Roedel , KVM , linux-s390 , "Michael S. Tsirkin" , Sebastian Ott , "linux-kernel@vger.kernel.org" , Christoph Hellwig , Christian Borntraeger , Andy Lutomirski , sparclinux@vger.kernel.org, Paolo Bonzini , Linux Virtualization , David Woodhouse , "David S. Miller" , Martin Schwidefsky On Mon, 2015-11-09 at 18:18 -0800, Andy Lutomirski wrote: > > Which leaves the special case of Xen, where even preexisting devices > don't bypass the IOMMU.  Can we keep this specific to powerpc and > sparc?  On x86, this problem is basically nonexistent, since the IOMMU > is properly self-describing. > > IOW, I think that on x86 we should assume that all virtio devices > honor the IOMMU. You don't like performances ? :-) Cheers, Ben.