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=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,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 A764DC433E0 for ; Wed, 27 Jan 2021 15:51:36 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1E419207B7 for ; Wed, 27 Jan 2021 15:51:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1E419207B7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:39278 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l4n6U-00008R-PX for qemu-devel@archiver.kernel.org; Wed, 27 Jan 2021 10:51:34 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:40928) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l4n3F-0005So-9j for qemu-devel@nongnu.org; Wed, 27 Jan 2021 10:48:13 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:42842) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l4n3C-0001oS-MA for qemu-devel@nongnu.org; Wed, 27 Jan 2021 10:48:13 -0500 Received: from pps.filterd (m0098396.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 10RF3QMe162674 for ; Wed, 27 Jan 2021 10:48:08 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=reply-to : subject : to : cc : references : from : message-id : date : mime-version : in-reply-to : content-type : content-transfer-encoding; s=pp1; bh=6ZhfGTmXCOGIA3+UNkaw7nna0HMgiCZVOcU3Hiz8Wmc=; b=KoFvJau5FtKwPbTf3BW8RVFen0Np1G4dyHnhBUjzVLDwOv+wyAPn5dLpdY1ARWRVNXUI z+gOMuaQdIywzYMpPpnyY7uXvUIKWPcojdtCcJU8t+GJtKXHEvjwFWT5ohi+OUJIXFm8 KPd02QqRXzXTK1L8m7sgJvL87+U/iSY+0KXo4eSwSXHQBkKnlDl9kuzb+YmOsODrUI5a iGo/X1MPk1Po3pKgNa7duqu3WomnO2T4SnMyYxsBeEffO8o/YwWoKEnqP+Jk8It1Hf9E 6LV+FROh9rYlQLFlfpQ7TGKHbyfYh13F6TPvfiH/fTkEHRuBlhQa8OU1O8F6wpY+6dOy vw== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 36b3kfxk7u-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 27 Jan 2021 10:48:08 -0500 Received: from m0098396.ppops.net (m0098396.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 10RF3u8o166350 for ; Wed, 27 Jan 2021 10:48:08 -0500 Received: from ppma01dal.us.ibm.com (83.d6.3fa9.ip4.static.sl-reverse.com [169.63.214.131]) by mx0a-001b2d01.pphosted.com with ESMTP id 36b3kfxk6v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 27 Jan 2021 10:48:08 -0500 Received: from pps.filterd (ppma01dal.us.ibm.com [127.0.0.1]) by ppma01dal.us.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 10RFktxb002514; Wed, 27 Jan 2021 15:48:06 GMT Received: from b01cxnp22035.gho.pok.ibm.com (b01cxnp22035.gho.pok.ibm.com [9.57.198.25]) by ppma01dal.us.ibm.com with ESMTP id 36adttw17q-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 27 Jan 2021 15:48:06 +0000 Received: from b01ledav005.gho.pok.ibm.com (b01ledav005.gho.pok.ibm.com [9.57.199.110]) by b01cxnp22035.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 10RFm6Yh29294866 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 27 Jan 2021 15:48:06 GMT Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 190D9AE062; Wed, 27 Jan 2021 15:48:06 +0000 (GMT) Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2448FAE05F; Wed, 27 Jan 2021 15:48:05 +0000 (GMT) Received: from lagarcia.br.ibm.com (unknown [9.85.165.159]) by b01ledav005.gho.pok.ibm.com (Postfix) with ESMTP; Wed, 27 Jan 2021 15:48:04 +0000 (GMT) Subject: Re: [PATCH] IOMMU and ATS not supported by vhost-user filesystem. To: Stefan Hajnoczi References: <20210127111938.GH299797@stefanha-x1.localdomain> From: =?UTF-8?Q?Leonardo_Augusto_Guimar=c3=a3es_Garcia?= Organization: IBM Message-ID: Date: Wed, 27 Jan 2021 12:48:04 -0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <20210127111938.GH299797@stefanha-x1.localdomain> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.343, 18.0.737 definitions=2021-01-27_05:2021-01-27, 2021-01-27 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 bulkscore=0 phishscore=0 mlxlogscore=999 lowpriorityscore=0 impostorscore=0 spamscore=0 adultscore=0 malwarescore=0 mlxscore=0 suspectscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2101270083 Received-SPF: pass client-ip=148.163.156.1; envelope-from=lagarcia@linux.ibm.com; helo=mx0a-001b2d01.pphosted.com X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: lagarcia@br.ibm.com Cc: maxime.coquelin@redhat.com, qemu-devel@nongnu.org, dgilbert@redhat.com, "Michael S. Tsirkin" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 1/27/21 8:19 AM, Stefan Hajnoczi wrote: > On Tue, Jan 26, 2021 at 03:23:38PM -0300, lagarcia@linux.ibm.com wrote: >> From: Leonardo Garcia >> >> Currently, as IOMMU and ATS are not supported, if a user mistakenly set >> any of them and tries to mount the vhost-user filesystem inside the >> guest, whenever the user tries to access the mount point, the system >> will hang forever. >> >> Signed-off-by: Leonardo Garcia >> --- >> hw/virtio/vhost-user-fs-pci.c | 7 +++++++ >> hw/virtio/vhost-user-fs.c | 5 +++++ >> 2 files changed, 12 insertions(+) >> >> diff --git a/hw/virtio/vhost-user-fs-pci.c b/hw/virtio/vhost-user-fs-pci.c >> index 2ed8492b3f..564d1fd108 100644 >> --- a/hw/virtio/vhost-user-fs-pci.c >> +++ b/hw/virtio/vhost-user-fs-pci.c >> @@ -11,6 +11,8 @@ >> * top-level directory. >> */ >> >> +#include "qemu/osdep.h" >> +#include "qapi/error.h" >> #include "qemu/osdep.h" >> #include "hw/qdev-properties.h" >> #include "hw/virtio/vhost-user-fs.h" >> @@ -45,6 +47,11 @@ static void vhost_user_fs_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp) >> vpci_dev->nvectors = dev->vdev.conf.num_request_queues + 2; >> } >> >> + if (vpci_dev->flags & VIRTIO_PCI_FLAG_ATS) { >> + error_setg(errp, "ATS is currently not supported with vhost-user-fs-pci"); >> + return; >> + } > Why is this check needed in addition to VIRTIO_F_IOMMU_PLATFORM? > > What needs to be added to support ATS? > >> + >> qdev_realize(vdev, BUS(&vpci_dev->bus), errp); >> } >> >> diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c >> index ac4fc34b36..914d68b3ee 100644 >> --- a/hw/virtio/vhost-user-fs.c >> +++ b/hw/virtio/vhost-user-fs.c >> @@ -203,6 +203,11 @@ static void vuf_device_realize(DeviceState *dev, Error **errp) >> return; >> } >> >> + if (virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM)) { >> + error_setg(errp, "IOMMU is currently not supported with vhost-user-fs"); >> + return; >> + } >> + >> if (!vhost_user_init(&fs->vhost_user, &fs->conf.chardev, errp)) { > I thought IOMMU support depends on the vhost-user device backend (e.g. > virtiofsd), so the vhost-user backend should participate in advertising > this feature. > > Perhaps the check should be: > > ret = vhost_dev_init(&fs->vhost_dev, &fs->vhost_user, > VHOST_BACKEND_TYPE_USER, 0); > if (ret < 0) { > error_setg_errno(errp, -ret, "vhost_dev_init failed"); > goto err_virtio; > } > + > + if (virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM) && > + !(fs->vhost_dev.hdev_features & (1ull << VIRTIO_F_IOMMU_PLATFORM))) { > + error_setg(errp, "IOMMU is not supported by the vhost-user device backend"); > + goto err_iommu_needed; > + } > > Also, can this logic be made generic for all vhost-user devices? It's > not really specific to vhost-user-fs. Further analyzing this, on vhost-user.c, I see:         if (virtio_has_feature(features, VIRTIO_F_IOMMU_PLATFORM) &&                 !(virtio_has_feature(dev->protocol_features,                     VHOST_USER_PROTOCOL_F_SLAVE_REQ) &&                  virtio_has_feature(dev->protocol_features,                     VHOST_USER_PROTOCOL_F_REPLY_ACK))) {             error_report("IOMMU support requires reply-ack and "                          "slave-req protocol features.");             return -1;         } This code was included by commit 6dcdd06. It included support for VIRTIO_F_IOMMU_PLATFORM with vhost_net devices. So, the restriction is not generic for all vhost-user devices. Cheers, Leo > > Stefan