From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 90FE2C4646D for ; Tue, 7 Aug 2018 00:34:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3FDB221A64 for ; Tue, 7 Aug 2018 00:34:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3FDB221A64 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.crashing.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387606AbeHGCqe (ORCPT ); Mon, 6 Aug 2018 22:46:34 -0400 Received: from gate.crashing.org ([63.228.1.57]:42454 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731096AbeHGCqe (ORCPT ); Mon, 6 Aug 2018 22:46:34 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id w770I8LZ016015; Mon, 6 Aug 2018 19:18:09 -0500 Message-ID: <53554e339b334b47d5822fb5219d5c878674b33c.camel@kernel.crashing.org> Subject: Re: [RFC 0/4] Virtio uses DMA API for all devices From: Benjamin Herrenschmidt To: "Michael S. Tsirkin" Cc: Christoph Hellwig , Will Deacon , Anshuman Khandual , virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, aik@ozlabs.ru, robh@kernel.org, joe@perches.com, elfring@users.sourceforge.net, david@gibson.dropbear.id.au, jasowang@redhat.com, mpe@ellerman.id.au, linuxram@us.ibm.com, haren@linux.vnet.ibm.com, paulus@samba.org, srikar@linux.vnet.ibm.com, robin.murphy@arm.com, jean-philippe.brucker@arm.com, marc.zyngier@arm.com Date: Tue, 07 Aug 2018 10:18:07 +1000 In-Reply-To: <20180807024503-mutt-send-email-mst@kernel.org> References: <20180803220443-mutt-send-email-mst@kernel.org> <051fd78e15595b414839fa8f9d445b9f4d7576c6.camel@kernel.crashing.org> <20180805031046-mutt-send-email-mst@kernel.org> <20180806164106-mutt-send-email-mst@kernel.org> <20180806233024-mutt-send-email-mst@kernel.org> <0967fc30001323e6e38ed12c8dba8ee3d1aa13f5.camel@kernel.crashing.org> <20180807002857-mutt-send-email-mst@kernel.org> <93518075238a07e9f011774d89bdc652c083f1ba.camel@kernel.crashing.org> <20180807024503-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.4 (3.28.4-1.fc28) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2018-08-07 at 02:45 +0300, Michael S. Tsirkin wrote: > > OK well, assuming Christoph can solve the direct case in a way that > > also work for the virtio !iommu case, we still want some bit of logic > > somewhere that will "switch" to swiotlb based ops if the DMA mask is > > limited. > > > > You mentioned an RFC for that ? Do you happen to have a link ? > > No but Christoph did I think. Ok I missed that, sorry, I'll dig it out. Thanks. Cheers, Ben.