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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,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 B0B9AC433DF for ; Thu, 9 Jul 2020 10:52:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 935A72074B for ; Thu, 9 Jul 2020 10:52:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726908AbgGIKwN (ORCPT ); Thu, 9 Jul 2020 06:52:13 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:47754 "EHLO mx0b-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726339AbgGIKwN (ORCPT ); Thu, 9 Jul 2020 06:52:13 -0400 Received: from pps.filterd (m0127361.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 069AX7Cc090673; Thu, 9 Jul 2020 06:52:05 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 325wbv7gtj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 09 Jul 2020 06:52:05 -0400 Received: from m0127361.ppops.net (m0127361.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 069AXgrM091981; Thu, 9 Jul 2020 06:52:04 -0400 Received: from ppma04fra.de.ibm.com (6a.4a.5195.ip4.static.sl-reverse.com [149.81.74.106]) by mx0a-001b2d01.pphosted.com with ESMTP id 325wbv7gt1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 09 Jul 2020 06:52:04 -0400 Received: from pps.filterd (ppma04fra.de.ibm.com [127.0.0.1]) by ppma04fra.de.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 069ApOtI015883; Thu, 9 Jul 2020 10:52:02 GMT Received: from b06cxnps4076.portsmouth.uk.ibm.com (d06relay13.portsmouth.uk.ibm.com [9.149.109.198]) by ppma04fra.de.ibm.com with ESMTP id 325k2drdgf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 09 Jul 2020 10:52:02 +0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 069Apxrw46727170 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 9 Jul 2020 10:51:59 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8A50FAE056; Thu, 9 Jul 2020 10:51:59 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B4B58AE051; Thu, 9 Jul 2020 10:51:58 +0000 (GMT) Received: from oc3016276355.ibm.com (unknown [9.145.34.67]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 9 Jul 2020 10:51:58 +0000 (GMT) Subject: Re: [PATCH v5 2/2] s390: virtio: PV needs VIRTIO I/O device protection To: Cornelia Huck Cc: linux-kernel@vger.kernel.org, pasic@linux.ibm.com, borntraeger@de.ibm.com, frankja@linux.ibm.com, mst@redhat.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: <1594283959-13742-1-git-send-email-pmorel@linux.ibm.com> <1594283959-13742-3-git-send-email-pmorel@linux.ibm.com> <20200709105733.6d68fa53.cohuck@redhat.com> From: Pierre Morel Message-ID: <270d8674-0f73-0a38-a2a7-fbc1caa44301@linux.ibm.com> Date: Thu, 9 Jul 2020 12:51:58 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: <20200709105733.6d68fa53.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=2020-07-09_05:2020-07-09,2020-07-09 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 mlxlogscore=999 clxscore=1015 priorityscore=1501 lowpriorityscore=0 malwarescore=0 phishscore=0 suspectscore=0 adultscore=0 spamscore=0 impostorscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007090084 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-07-09 10:57, Cornelia Huck wrote: > On Thu, 9 Jul 2020 10:39:19 +0200 > Pierre Morel wrote: > >> If protected virtualization is active on s390, the virtio queues are >> not accessible to the host, unless VIRTIO_F_IOMMU_PLATFORM has been >> negotiated. Use the new arch_validate_virtio_features() interface to >> fail probe if that's not the case, preventing a host error on access >> attempt >> >> Signed-off-by: Pierre Morel >> --- >> arch/s390/mm/init.c | 27 +++++++++++++++++++++++++++ >> 1 file changed, 27 insertions(+) >> >> diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c >> index 6dc7c3b60ef6..b8e6f90117da 100644 >> --- a/arch/s390/mm/init.c >> +++ b/arch/s390/mm/init.c >> @@ -45,6 +45,7 @@ >> #include >> #include >> #include >> +#include >> >> pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(.bss..swapper_pg_dir); >> >> @@ -161,6 +162,32 @@ bool force_dma_unencrypted(struct device *dev) >> return is_prot_virt_guest(); >> } >> >> +/* >> + * arch_validate_virtio_features >> + * @dev: the VIRTIO device being added >> + * >> + * Return an error if required features are missing on a guest running >> + * with protected virtualization. >> + */ >> +int arch_validate_virtio_features(struct virtio_device *dev) >> +{ >> + if (!is_prot_virt_guest()) >> + return 0; >> + >> + if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1)) { >> + dev_warn(&dev->dev, "device must provide VIRTIO_F_VERSION_1\n"); > > I'd probably use "legacy virtio not supported with protected > virtualization". > >> + return -ENODEV; >> + } >> + >> + if (!virtio_has_feature(dev, VIRTIO_F_IOMMU_PLATFORM)) { >> + dev_warn(&dev->dev, >> + "device must provide VIRTIO_F_IOMMU_PLATFORM\n"); > > "support for limited memory access required for protected > virtualization" > > ? > > Mentioning the feature flag is shorter in both cases, though. And I think easier to look for in case of debugging purpose. I change it if there is more demands. > >> + return -ENODEV; >> + } >> + >> + return 0; >> +} >> + >> /* protected virtualization */ >> static void pv_init(void) >> { > > Either way, > > Reviewed-by: Cornelia Huck > Thanks, Pierre -- Pierre Morel IBM Lab Boeblingen