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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 D2EC2C43381 for ; Fri, 15 Mar 2019 18:16:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A6353218AC for ; Fri, 15 Mar 2019 18:16:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726452AbfCOSQK (ORCPT ); Fri, 15 Mar 2019 14:16:10 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:33258 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725910AbfCOSQJ (ORCPT ); Fri, 15 Mar 2019 14:16:09 -0400 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x2FIA6Ob079093 for ; Fri, 15 Mar 2019 14:16:08 -0400 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0a-001b2d01.pphosted.com with ESMTP id 2r8gse15dm-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 15 Mar 2019 14:16:07 -0400 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 15 Mar 2019 18:16:05 -0000 Received: from b06cxnps4075.portsmouth.uk.ibm.com (9.149.109.197) by e06smtp05.uk.ibm.com (192.168.101.135) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Fri, 15 Mar 2019 18:16:02 -0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x2FIG0d629229120 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 15 Mar 2019 18:16:01 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D32EE4C040; Fri, 15 Mar 2019 18:16:00 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6D9D94C058; Fri, 15 Mar 2019 18:16:00 +0000 (GMT) Received: from oc2783563651 (unknown [9.152.224.177]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 15 Mar 2019 18:16:00 +0000 (GMT) Date: Fri, 15 Mar 2019 19:15:57 +0100 From: Halil Pasic To: Pierre Morel Cc: borntraeger@de.ibm.com, alex.williamson@redhat.com, cohuck@redhat.com, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, kvm@vger.kernel.org, frankja@linux.ibm.com, akrowiak@linux.ibm.com, david@redhat.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, freude@linux.ibm.com, mimu@linux.ibm.com Subject: Re: [PATCH v5 4/7] s390: ap: setup relation betwen KVM and mediated device In-Reply-To: <1552493104-30510-5-git-send-email-pmorel@linux.ibm.com> References: <1552493104-30510-1-git-send-email-pmorel@linux.ibm.com> <1552493104-30510-5-git-send-email-pmorel@linux.ibm.com> Organization: IBM X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.31; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 19031518-0020-0000-0000-00000323D24D X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19031518-0021-0000-0000-00002175DD38 Message-Id: <20190315191557.6c8d7668@oc2783563651> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-03-15_12:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1903150125 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 13 Mar 2019 17:05:01 +0100 Pierre Morel wrote: > When the mediated device is open we setup the relation with KVM unset it > when the mediated device is released. > > We ensure KVM is present on opening of the mediated device. > > We ensure that KVM survives the mediated device, and establish a direct survives? > link from KVM to the mediated device to simplify the relationship. > > Signed-off-by: Pierre Morel > --- > drivers/s390/crypto/vfio_ap_ops.c | 80 ++++++++++++++++++++++----------------- > 1 file changed, 46 insertions(+), 34 deletions(-) > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > index 0f8952c23..6b559ca 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -790,7 +790,6 @@ static int vfio_ap_mdev_iommu_notifier(struct notifier_block *nb, > * vfio_ap_mdev_set_kvm > * > * @matrix_mdev: a mediated matrix device > - * @kvm: reference to KVM instance > * > * Verifies no other mediated matrix device has @kvm and sets a reference to > * it in @matrix_mdev->kvm. > @@ -798,53 +797,39 @@ static int vfio_ap_mdev_iommu_notifier(struct notifier_block *nb, > * Return 0 if no other mediated matrix device has a reference to @kvm; > * otherwise, returns an -EPERM. > */ > -static int vfio_ap_mdev_set_kvm(struct ap_matrix_mdev *matrix_mdev, > - struct kvm *kvm) > +static int vfio_ap_mdev_set_kvm(struct ap_matrix_mdev *matrix_mdev) > { > - struct ap_matrix_mdev *m; > - > mutex_lock(&matrix_dev->lock); > + if (matrix_mdev->kvm->arch.crypto.pqap_hook) > + goto err_unlock; > > - list_for_each_entry(m, &matrix_dev->mdev_list, node) { > - if ((m != matrix_mdev) && (m->kvm == kvm)) { > - mutex_unlock(&matrix_dev->lock); > - return -EPERM; > - } > - } > + if (!matrix_mdev->kvm->arch.crypto.crycbd) > + goto err_unlock; > > - matrix_mdev->kvm = kvm; > - mutex_unlock(&matrix_dev->lock); > + matrix_mdev->kvm->arch.crypto.pqap_hook = &matrix_mdev->pqap_hook; > > + kvm_arch_crypto_set_masks(matrix_mdev->kvm, matrix_mdev->matrix.apm, > + matrix_mdev->matrix.aqm, > + matrix_mdev->matrix.adm); > + kvm_get_kvm(matrix_mdev->kvm); > + mutex_unlock(&matrix_dev->lock); > return 0; > + > +err_unlock: > + mutex_unlock(&matrix_dev->lock); > + return -EPERM; > } > > static int vfio_ap_mdev_group_notifier(struct notifier_block *nb, > unsigned long action, void *data) > { > - int ret; > struct ap_matrix_mdev *matrix_mdev; > > if (action != VFIO_GROUP_NOTIFY_SET_KVM) > return NOTIFY_OK; > > matrix_mdev = container_of(nb, struct ap_matrix_mdev, group_notifier); > - > - if (!data) { > - matrix_mdev->kvm = NULL; > - return NOTIFY_OK; > - } > - > - ret = vfio_ap_mdev_set_kvm(matrix_mdev, data); > - if (ret) > - return NOTIFY_DONE; > - > - /* If there is no CRYCB pointer, then we can't copy the masks */ > - if (!matrix_mdev->kvm->arch.crypto.crycbd) > - return NOTIFY_DONE; > - > - kvm_arch_crypto_set_masks(matrix_mdev->kvm, matrix_mdev->matrix.apm, > - matrix_mdev->matrix.aqm, > - matrix_mdev->matrix.adm); > + matrix_mdev->kvm = data; > > return NOTIFY_OK; > } > @@ -888,6 +873,12 @@ static int vfio_ap_mdev_open(struct mdev_device *mdev) > if (ret) > goto err_group; > > + /* We do not support opening the mediated device without KVM */ > + if (!matrix_mdev->kvm) { > + ret = -ENODEV; > + goto err_group; > + } > + > matrix_mdev->iommu_notifier.notifier_call = vfio_ap_mdev_iommu_notifier; > events = VFIO_IOMMU_NOTIFY_DMA_UNMAP; > > @@ -896,8 +887,15 @@ static int vfio_ap_mdev_open(struct mdev_device *mdev) > if (ret) > goto err_iommu; > > + ret = vfio_ap_mdev_set_kvm(matrix_mdev); At this point the matrix_mdev->kvm ain't guaranteed to be valid IMHO. Or am I wrong? If I'm right kvm_get_kvm(matrix_mdev->kvm) could be too late. > + if (ret) > + goto err_kvm; > + > return 0; > > +err_kvm: > + vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, > + &matrix_mdev->iommu_notifier); > err_iommu: > vfio_unregister_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY, > &matrix_mdev->group_notifier); > @@ -906,19 +904,33 @@ static int vfio_ap_mdev_open(struct mdev_device *mdev) > return ret; > } > > -static void vfio_ap_mdev_release(struct mdev_device *mdev) > +static int vfio_ap_mdev_unset_kvm(struct ap_matrix_mdev *matrix_mdev) > { > - struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); > + struct kvm *kvm = matrix_mdev->kvm; > > if (matrix_mdev->kvm) > kvm_arch_crypto_clear_masks(matrix_mdev->kvm); This still conditional? > - > + vfio_ap_mdev_reset_queues(matrix_mdev->mdev); I guess your intention was to move vfio_ap_mdev_reset_queues() here from vfio_ap_mdev_release(), but you still have a vfio_ap_mdev_reset_queues() call in vfio_ap_mdev_release(). > + matrix_mdev->kvm->arch.crypto.pqap_hook = NULL; > matrix_mdev->kvm = NULL; > + > + kvm_put_kvm(kvm); > + return 0; > +} > + > +static void vfio_ap_mdev_release(struct mdev_device *mdev) > +{ > + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); > + > + mutex_lock(&matrix_dev->lock); > + > vfio_ap_mdev_reset_queues(mdev); Here. Regards, Halil > + vfio_ap_mdev_unset_kvm(matrix_mdev); > vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, > &matrix_mdev->iommu_notifier); > vfio_unregister_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY, > &matrix_mdev->group_notifier); > + mutex_unlock(&matrix_dev->lock); > module_put(THIS_MODULE); > } >