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=-5.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 523BAC433DF for ; Thu, 2 Jul 2020 13:05:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2A0E12073E for ; Thu, 2 Jul 2020 13:05:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729141AbgGBNFd (ORCPT ); Thu, 2 Jul 2020 09:05:33 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:63050 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726343AbgGBNFc (ORCPT ); Thu, 2 Jul 2020 09:05:32 -0400 Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 062D51uS049499; Thu, 2 Jul 2020 09:05:26 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 3212atdq6n-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 02 Jul 2020 09:05:25 -0400 Received: from m0098394.ppops.net (m0098394.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 062D5Orp052085; Thu, 2 Jul 2020 09:05:24 -0400 Received: from ppma01fra.de.ibm.com (46.49.7a9f.ip4.static.sl-reverse.com [159.122.73.70]) by mx0a-001b2d01.pphosted.com with ESMTP id 3212atdpfk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 02 Jul 2020 09:05:21 -0400 Received: from pps.filterd (ppma01fra.de.ibm.com [127.0.0.1]) by ppma01fra.de.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 062Cso7p024179; Thu, 2 Jul 2020 13:03:55 GMT Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by ppma01fra.de.ibm.com with ESMTP id 31wyyaun24-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 02 Jul 2020 13:03:55 +0000 Received: from d06av25.portsmouth.uk.ibm.com (d06av25.portsmouth.uk.ibm.com [9.149.105.61]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 062D3q0N58196058 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 2 Jul 2020 13:03:52 GMT Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C053511C052; Thu, 2 Jul 2020 13:03:52 +0000 (GMT) Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id F257411C04C; Thu, 2 Jul 2020 13:03:51 +0000 (GMT) Received: from oc3016276355.ibm.com (unknown [9.145.146.43]) by d06av25.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 2 Jul 2020 13:03:51 +0000 (GMT) Subject: Re: [PATCH v3 1/1] s390: virtio: let arch accept devices without IOMMU feature To: Cornelia Huck , "Michael S. Tsirkin" Cc: linux-kernel@vger.kernel.org, pasic@linux.ibm.com, borntraeger@de.ibm.com, frankja@linux.ibm.com, jasowang@redhat.com, kvm@vger.kernel.org, linux-s390@vger.kernel.org, virtualization@lists.linux-foundation.org, thomas.lendacky@amd.com, david@gibson.dropbear.id.au, linuxram@us.ibm.com, heiko.carstens@de.ibm.com, gor@linux.ibm.com References: <1592390637-17441-1-git-send-email-pmorel@linux.ibm.com> <1592390637-17441-2-git-send-email-pmorel@linux.ibm.com> <20200629115651-mutt-send-email-mst@kernel.org> <20200629180526.41d0732b.cohuck@redhat.com> From: Pierre Morel Message-ID: <26ecd4c6-837b-1ce6-170b-a0155e4dd4d4@linux.ibm.com> Date: Thu, 2 Jul 2020 15:03:51 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200629180526.41d0732b.cohuck@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235,18.0.687 definitions=2020-07-02_08:2020-07-02,2020-07-02 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 cotscore=-2147483648 spamscore=0 priorityscore=1501 malwarescore=0 clxscore=1015 phishscore=0 mlxlogscore=881 suspectscore=0 lowpriorityscore=0 mlxscore=0 adultscore=0 impostorscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2007020094 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-06-29 18:05, Cornelia Huck wrote: > On Mon, 29 Jun 2020 11:57:14 -0400 > "Michael S. Tsirkin" wrote: > >> On Wed, Jun 17, 2020 at 12:43:57PM +0200, Pierre Morel wrote: >>> An architecture protecting the guest memory against unauthorized host >>> access may want to enforce VIRTIO I/O device protection through the >>> use of VIRTIO_F_IOMMU_PLATFORM. >>> >>> Let's give a chance to the architecture to accept or not devices >>> without VIRTIO_F_IOMMU_PLATFORM. >>> >>> Signed-off-by: Pierre Morel >>> Acked-by: Jason Wang >>> Acked-by: Christian Borntraeger >>> --- >>> arch/s390/mm/init.c | 6 ++++++ >>> drivers/virtio/virtio.c | 22 ++++++++++++++++++++++ >>> include/linux/virtio.h | 2 ++ >>> 3 files changed, 30 insertions(+) > >>> @@ -179,6 +194,13 @@ int virtio_finalize_features(struct virtio_device *dev) >>> if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1)) >>> return 0; >>> >>> + if (arch_needs_virtio_iommu_platform(dev) && >>> + !virtio_has_feature(dev, VIRTIO_F_IOMMU_PLATFORM)) { >>> + dev_warn(&dev->dev, >>> + "virtio: device must provide VIRTIO_F_IOMMU_PLATFORM\n"); >>> + return -ENODEV; >>> + } >>> + >>> virtio_add_status(dev, VIRTIO_CONFIG_S_FEATURES_OK); >>> status = dev->config->get_status(dev); >>> if (!(status & VIRTIO_CONFIG_S_FEATURES_OK)) { >> >> Well don't you need to check it *before* VIRTIO_F_VERSION_1, not after? > > But it's only available with VERSION_1 anyway, isn't it? So it probably > also needs to fail when this feature is needed if VERSION_1 has not been > negotiated, I think. > Yes, clearly, I will add this. Thanks, Pierre -- Pierre Morel IBM Lab Boeblingen