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Received-SPF: Pass (protection.outlook.com: domain of amd.com designates 165.204.84.17 as permitted sender) receiver=protection.outlook.com; client-ip=165.204.84.17; helo=SATLEXMB04.amd.com; pr=C Received: from SATLEXMB04.amd.com (165.204.84.17) by CO1NAM11FT035.mail.protection.outlook.com (10.13.175.36) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.20.6111.21 via Frontend Transport; Mon, 20 Feb 2023 19:02:26 +0000 Received: from localhost (10.180.168.240) by SATLEXMB04.amd.com (10.181.40.145) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.34; Mon, 20 Feb 2023 13:02:25 -0600 From: Michael Roth To: CC: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Vishal Annapurve Subject: [PATCH RFC v8 07/56] KVM: SEV: Populate private memory fd during LAUNCH_UPDATE_DATA Date: Mon, 20 Feb 2023 12:37:58 -0600 Message-ID: <20230220183847.59159-8-michael.roth@amd.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230220183847.59159-1-michael.roth@amd.com> References: <20230220183847.59159-1-michael.roth@amd.com> MIME-Version: 1.0 X-Originating-IP: [10.180.168.240] X-ClientProxiedBy: SATLEXMB03.amd.com (10.181.40.144) To SATLEXMB04.amd.com (10.181.40.145) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1NAM11FT035:EE_|DS0PR12MB8561:EE_ X-MS-Office365-Filtering-Correlation-Id: 607fe171-2f6f-4e08-2f07-08db137501ba X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Feb 2023 19:02:26.2418 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 607fe171-2f6f-4e08-2f07-08db137501ba X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[SATLEXMB04.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CO1NAM11FT035.eop-nam11.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB8561 X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 973D8C0016 X-Rspam-User: X-Stat-Signature: hgkac166p8mx4upx3hsggha7ji8iobfm X-HE-Tag: 1676919748-429062 X-HE-Meta: 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 6dqRNxOh HSH3LRDCXnxD/VNp4b1rwnt84uBug7XgI8FfNsStLNBgHg+zW8QkneObPjVBC3JIycVidv7D0sFYSH9GLACi+cGkIGZoqLrwOLwlh5BwTSLyBWOS8eAZVxMqSAXbgQGWOfjPX89m88MgtkkhL2xdVtMI+t/CmFGx7VmRgpPAD+lGqlTCtJoYHU2mALjMzG6qX8mp/My9rslSIxmQSK4uYsaxLzS/Un3tiYNcW5bGeS3LTtesI8JrandQjqkgwOYS+fFtnF1DiJ3M+Sba62tXbsGass5movGBZ9aOnJmT8oSwRMhccJCdWdgWbgVKXfzF8CN9UdObRioENv2RShwLB085Ga1A3Z3k0rVYln3IEtj9MpkwG66+RGQhWt7aAxH6OzeC0XsrVhdy122U= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Vishal Annapurve This change adds handling of HVA ranges to copy contents to private memory while doing sev launch update data. mem_attr array is updated during LAUNCH_UPDATE_DATA to ensure that encrypted memory is marked as private. Signed-off-by: Vishal Annapurve [mdr: Use gfn_to_hva_memslot_prot() for shared GFN handler to deal with read-only slots for ROMs. Split kvm_vm_set_region_attr into separate patch.] Signed-off-by: Michael Roth --- arch/x86/kvm/svm/sev.c | 103 +++++++++++++++++++++++++++++++++++++---- virt/kvm/kvm_main.c | 2 + 2 files changed, 96 insertions(+), 9 deletions(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 273cba809328..fad7fb34ef9e 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -494,23 +494,26 @@ static unsigned long get_num_contig_pages(unsigned long idx, return pages; } -static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) +static int sev_launch_update_shared_gfn_handler(struct kvm *kvm, + struct kvm_gfn_range *range, + struct kvm_sev_cmd *argp) { unsigned long vaddr, vaddr_end, next_vaddr, npages, pages, size, i; struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; - struct kvm_sev_launch_update_data params; struct sev_data_launch_update_data data; struct page **inpages; int ret; - if (!sev_guest(kvm)) - return -ENOTTY; - - if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) - return -EFAULT; + vaddr = gfn_to_hva_memslot_prot(range->slot, range->start, NULL); + pr_debug("%s: shared GFN: %llx, slot.id: %d, slot.base_gfn: %llx, slot.userspace_addr: %lx, slot.flags: %x, vaddr: %lx\n", + __func__, range->start, range->slot->id, range->slot->base_gfn, + range->slot->userspace_addr, range->slot->flags, vaddr); + if (kvm_is_error_hva(vaddr)) { + pr_err("vaddr is erroneous 0x%lx\n", vaddr); + return -EINVAL; + } - vaddr = params.uaddr; - size = params.len; + size = (range->end - range->start) << PAGE_SHIFT; vaddr_end = vaddr + size; /* Lock the user memory. */ @@ -562,6 +565,88 @@ static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) return ret; } +static int sev_launch_update_priv_gfn_handler(struct kvm *kvm, + struct kvm_gfn_range *range, + struct kvm_sev_cmd *argp) +{ + struct sev_data_launch_update_data data; + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; + gfn_t gfn; + kvm_pfn_t pfn; + struct kvm_memory_slot *memslot = range->slot; + int ret = 0; + + data.reserved = 0; + data.handle = sev->handle; + + for (gfn = range->start; gfn < range->end; gfn++) { + int order; + void *kvaddr; + + ret = kvm_restrictedmem_get_pfn(memslot, gfn, &pfn, &order); + if (ret) + goto e_ret; + + kvaddr = pfn_to_kaddr(pfn); + if (!virt_addr_valid(kvaddr)) { + pr_debug("%s: Invalid kvaddr 0x%llx\n", __func__, (uint64_t)kvaddr); + ret = -EINVAL; + goto e_ret; + } + + ret = kvm_read_guest_page(kvm, gfn, kvaddr, 0, PAGE_SIZE); + if (ret) { + pr_debug("%s: Guest read failed 0x%x\n", __func__, ret); + goto e_ret; + } + + if (!cpu_feature_enabled(X86_FEATURE_SME_COHERENT)) + clflush_cache_range(kvaddr, PAGE_SIZE); + + data.len = PAGE_SIZE; + data.address = __sme_set(pfn << PAGE_SHIFT); + ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_DATA, &data, &argp->error); + if (ret) + goto e_ret; + kvm_release_pfn_clean(pfn); + } + + /* + * Memory attribute updates via KVM_SET_MEMORY_ATTRIBUTES are serialized + * via kvm->slots_lock, so use the same protocol for updating them here. + */ + mutex_lock(&kvm->slots_lock); + kvm_vm_set_region_attr(kvm, range->start, range->end, KVM_MEMORY_ATTRIBUTE_PRIVATE); + mutex_unlock(&kvm->slots_lock); +e_ret: + return ret; +} + +static int sev_launch_update_gfn_handler(struct kvm *kvm, struct kvm_gfn_range *range, + void *data) +{ + struct kvm_sev_cmd *argp = (struct kvm_sev_cmd *)data; + + if (kvm_slot_can_be_private(range->slot)) + return sev_launch_update_priv_gfn_handler(kvm, range, argp); + + return sev_launch_update_shared_gfn_handler(kvm, range, argp); +} + +static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) +{ + struct kvm_sev_launch_update_data params; + + if (!sev_guest(kvm)) + return -ENOTTY; + + if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, sizeof(params))) + return -EFAULT; + + return kvm_vm_do_hva_range_op(kvm, params.uaddr, params.uaddr + params.len, + sev_launch_update_gfn_handler, argp); +} + static int sev_es_sync_vmsa(struct vcpu_svm *svm) { struct sev_es_save_area *save = svm->sev_es.vmsa; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index c740b56d6ba4..003cb199ba4b 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -689,6 +689,7 @@ int kvm_vm_do_hva_range_op(struct kvm *kvm, unsigned long hva_start, return ret; } +EXPORT_SYMBOL_GPL(kvm_vm_do_hva_range_op); static __always_inline int kvm_handle_hva_range(struct mmu_notifier *mn, unsigned long start, @@ -2850,6 +2851,7 @@ unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot, return hva; } +EXPORT_SYMBOL_GPL(gfn_to_hva_memslot_prot); unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable) {