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=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, 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 61876C43331 for ; Thu, 2 Apr 2020 20:16:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 219CA20678 for ; Thu, 2 Apr 2020 20:16:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="vp8/zSGo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389248AbgDBUQQ (ORCPT ); Thu, 2 Apr 2020 16:16:16 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:58094 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730837AbgDBUQP (ORCPT ); Thu, 2 Apr 2020 16:16:15 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 032KCiuv056647; Thu, 2 Apr 2020 20:15:54 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : to : cc : references : from : message-id : date : mime-version : in-reply-to : content-type : content-transfer-encoding; s=corp-2020-01-29; bh=ez2ChUkx4xOH2a6lM2XxI8VM0HIEOBcTbzuLjiyX+7E=; b=vp8/zSGoUaYFIg2wXwoqNYAim0xuLLYTGftz6veJdOx7Q7y7h1YCb1bRo1Rsr4gjKiDc 4AwDOu3K8e7D7nvd7LbsRDGGf2CJme9wGSu0rxavbfyqSV9nBWi4qnjBPKeczWDPMONt zS4bUNYluzlZSCAyCLmhb3hYGgzk8YiLAMZ+ZMK8QlupkgbPLgMsJ7PhIcoiq/tGmo4u GtCYr0X2g1zXCBXlByIwIinoLo/AB4ltFBRlkXZwGUiz/vv93OF7yW2zlWRQiHij+zjP 4ySwz4Dq7tS1RCExkz97NbVlRm73gwQ7BkASusMQF4KFV1TeswIS6zfk/PHmJkPuokE6 VQ== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by userp2120.oracle.com with ESMTP id 303aqhx4wc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 02 Apr 2020 20:15:53 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 032KCMeV157458; Thu, 2 Apr 2020 20:13:52 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserp3030.oracle.com with ESMTP id 302g4w3g2m-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 02 Apr 2020 20:13:52 +0000 Received: from abhmp0020.oracle.com (abhmp0020.oracle.com [141.146.116.26]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 032KDnLx013309; Thu, 2 Apr 2020 20:13:49 GMT Received: from localhost.localdomain (/10.159.142.52) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 02 Apr 2020 13:13:49 -0700 Subject: Re: [PATCH v6 02/14] KVM: SVM: Add KVM_SEND_UPDATE_DATA command To: Ashish Kalra , pbonzini@redhat.com Cc: tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, joro@8bytes.org, bp@suse.de, thomas.lendacky@amd.com, x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, rientjes@google.com, srutherford@google.com, luto@kernel.org, brijesh.singh@amd.com References: <7ea65c7852543a7cd4fb904db751bed859735a84.1585548051.git.ashish.kalra@amd.com> From: Krish Sadhukhan Message-ID: <4d666d0d-b5de-eabe-05a8-242144a1fe51@oracle.com> Date: Thu, 2 Apr 2020 13:13:47 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <7ea65c7852543a7cd4fb904db751bed859735a84.1585548051.git.ashish.kalra@amd.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9579 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 bulkscore=0 suspectscore=2 mlxscore=0 spamscore=0 malwarescore=0 mlxlogscore=999 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004020147 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9579 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 phishscore=0 clxscore=1015 malwarescore=0 impostorscore=0 mlxlogscore=999 spamscore=0 mlxscore=0 priorityscore=1501 lowpriorityscore=0 adultscore=0 suspectscore=2 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004020147 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/29/20 11:20 PM, Ashish Kalra wrote: > From: Brijesh Singh > > The command is used for encrypting the guest memory region using the encryption > context created with KVM_SEV_SEND_START. > > Cc: Thomas Gleixner > Cc: Ingo Molnar > Cc: "H. Peter Anvin" > Cc: Paolo Bonzini > Cc: "Radim Krčmář" > Cc: Joerg Roedel > Cc: Borislav Petkov > Cc: Tom Lendacky > Cc: x86@kernel.org > Cc: kvm@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Reviewed-by : Steve Rutherford > Signed-off-by: Brijesh Singh > Signed-off-by: Ashish Kalra > --- > .../virt/kvm/amd-memory-encryption.rst | 24 ++++ > arch/x86/kvm/svm.c | 136 +++++++++++++++++- > include/uapi/linux/kvm.h | 9 ++ > 3 files changed, 165 insertions(+), 4 deletions(-) > > diff --git a/Documentation/virt/kvm/amd-memory-encryption.rst b/Documentation/virt/kvm/amd-memory-encryption.rst > index 4fd34fc5c7a7..f46817ef7019 100644 > --- a/Documentation/virt/kvm/amd-memory-encryption.rst > +++ b/Documentation/virt/kvm/amd-memory-encryption.rst > @@ -290,6 +290,30 @@ Returns: 0 on success, -negative on error > __u32 session_len; > }; > > +11. KVM_SEV_SEND_UPDATE_DATA > +---------------------------- > + > +The KVM_SEV_SEND_UPDATE_DATA command can be used by the hypervisor to encrypt the > +outgoing guest memory region with the encryption context creating using > +KVM_SEV_SEND_START. > + > +Parameters (in): struct kvm_sev_send_update_data > + > +Returns: 0 on success, -negative on error > + > +:: > + > + struct kvm_sev_launch_send_update_data { > + __u64 hdr_uaddr; /* userspace address containing the packet header */ > + __u32 hdr_len; > + > + __u64 guest_uaddr; /* the source memory region to be encrypted */ > + __u32 guest_len; > + > + __u64 trans_uaddr; /* the destition memory region */ > + __u32 trans_len; > + }; > + > References > ========== > > diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c > index 63d172e974ad..8561c47cc4f9 100644 > --- a/arch/x86/kvm/svm.c > +++ b/arch/x86/kvm/svm.c > @@ -428,6 +428,7 @@ static DECLARE_RWSEM(sev_deactivate_lock); > static DEFINE_MUTEX(sev_bitmap_lock); > static unsigned int max_sev_asid; > static unsigned int min_sev_asid; > +static unsigned long sev_me_mask; > static unsigned long *sev_asid_bitmap; > static unsigned long *sev_reclaim_asid_bitmap; > #define __sme_page_pa(x) __sme_set(page_to_pfn(x) << PAGE_SHIFT) > @@ -1232,16 +1233,22 @@ static int avic_ga_log_notifier(u32 ga_tag) > static __init int sev_hardware_setup(void) > { > struct sev_user_data_status *status; > + u32 eax, ebx; > int rc; > > - /* Maximum number of encrypted guests supported simultaneously */ > - max_sev_asid = cpuid_ecx(0x8000001F); > + /* > + * Query the memory encryption information. > + * EBX: Bit 0:5 Pagetable bit position used to indicate encryption > + * (aka Cbit). > + * ECX: Maximum number of encrypted guests supported simultaneously. > + * EDX: Minimum ASID value that should be used for SEV guest. > + */ > + cpuid(0x8000001f, &eax, &ebx, &max_sev_asid, &min_sev_asid); Will max_sev_asid and the max number of guests supported be the same number always ? > > if (!max_sev_asid) > return 1; > > - /* Minimum ASID value that should be used for SEV guest */ > - min_sev_asid = cpuid_edx(0x8000001F); > + sev_me_mask = 1UL << (ebx & 0x3f); > > /* Initialize SEV ASID bitmaps */ > sev_asid_bitmap = bitmap_zalloc(max_sev_asid, GFP_KERNEL); > @@ -7274,6 +7281,124 @@ static int sev_send_start(struct kvm *kvm, struct kvm_sev_cmd *argp) > return ret; > } > > +/* Userspace wants to query either header or trans length. */ > +static int > +__sev_send_update_data_query_lengths(struct kvm *kvm, struct kvm_sev_cmd *argp, > + struct kvm_sev_send_update_data *params) > +{ > + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; > + struct sev_data_send_update_data *data; > + int ret; > + > + data = kzalloc(sizeof(*data), GFP_KERNEL_ACCOUNT); > + if (!data) > + return -ENOMEM; > + > + data->handle = sev->handle; > + ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, data, &argp->error); > + > + params->hdr_len = data->hdr_len; > + params->trans_len = data->trans_len; > + > + if (copy_to_user((void __user *)(uintptr_t)argp->data, params, > + sizeof(struct kvm_sev_send_update_data))) > + ret = -EFAULT; > + > + kfree(data); > + return ret; > +} > + > +static int sev_send_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp) > +{ > + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; > + struct sev_data_send_update_data *data; > + struct kvm_sev_send_update_data params; > + void *hdr, *trans_data; > + struct page **guest_page; > + unsigned long n; > + int ret, offset; > + > + if (!sev_guest(kvm)) > + return -ENOTTY; Do we need to check the following conditions here ?     "The platform must be in the PSTATE.WORKING state.      The guest must be in the GSTATE.SUPDATE state." > + > + if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data, > + sizeof(struct kvm_sev_send_update_data))) > + return -EFAULT; > + > + /* userspace wants to query either header or trans length */ > + if (!params.trans_len || !params.hdr_len) > + return __sev_send_update_data_query_lengths(kvm, argp, ¶ms); > + > + if (!params.trans_uaddr || !params.guest_uaddr || > + !params.guest_len || !params.hdr_uaddr) > + return -EINVAL; > + > + > + /* Check if we are crossing the page boundary */ > + offset = params.guest_uaddr & (PAGE_SIZE - 1); > + if ((params.guest_len + offset > PAGE_SIZE)) > + return -EINVAL; > + > + /* Pin guest memory */ > + guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK, > + PAGE_SIZE, &n, 0); > + if (!guest_page) > + return -EFAULT; > + > + /* allocate memory for header and transport buffer */ > + ret = -ENOMEM; > + hdr = kmalloc(params.hdr_len, GFP_KERNEL_ACCOUNT); > + if (!hdr) > + goto e_unpin; > + > + trans_data = kmalloc(params.trans_len, GFP_KERNEL_ACCOUNT); > + if (!trans_data) > + goto e_free_hdr; > + > + data = kzalloc(sizeof(*data), GFP_KERNEL); > + if (!data) > + goto e_free_trans_data; > + > + data->hdr_address = __psp_pa(hdr); > + data->hdr_len = params.hdr_len; > + data->trans_address = __psp_pa(trans_data); > + data->trans_len = params.trans_len; > + > + /* The SEND_UPDATE_DATA command requires C-bit to be always set. */ > + data->guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + > + offset; > + data->guest_address |= sev_me_mask; Why not name the variable 'sev_cbit_mask' instead of sev_me_mask ? > + data->guest_len = params.guest_len; > + data->handle = sev->handle; > + > + ret = sev_issue_cmd(kvm, SEV_CMD_SEND_UPDATE_DATA, data, &argp->error); > + > + if (ret) > + goto e_free; > + > + /* copy transport buffer to user space */ > + if (copy_to_user((void __user *)(uintptr_t)params.trans_uaddr, > + trans_data, params.trans_len)) { > + ret = -EFAULT; > + goto e_unpin; > + } > + > + /* Copy packet header to userspace. */ > + ret = copy_to_user((void __user *)(uintptr_t)params.hdr_uaddr, hdr, > + params.hdr_len); > + > +e_free: > + kfree(data); > +e_free_trans_data: > + kfree(trans_data); > +e_free_hdr: > + kfree(hdr); > +e_unpin: > + sev_unpin_memory(kvm, guest_page, n); > + > + return ret; > +} > + > static int svm_mem_enc_op(struct kvm *kvm, void __user *argp) > { > struct kvm_sev_cmd sev_cmd; > @@ -7321,6 +7446,9 @@ static int svm_mem_enc_op(struct kvm *kvm, void __user *argp) > case KVM_SEV_SEND_START: > r = sev_send_start(kvm, &sev_cmd); > break; > + case KVM_SEV_SEND_UPDATE_DATA: > + r = sev_send_update_data(kvm, &sev_cmd); > + break; > default: > r = -EINVAL; > goto out; > diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h > index 17bef4c245e1..d9dc81bb9c55 100644 > --- a/include/uapi/linux/kvm.h > +++ b/include/uapi/linux/kvm.h > @@ -1570,6 +1570,15 @@ struct kvm_sev_send_start { > __u32 session_len; > }; > > +struct kvm_sev_send_update_data { > + __u64 hdr_uaddr; > + __u32 hdr_len; > + __u64 guest_uaddr; > + __u32 guest_len; > + __u64 trans_uaddr; > + __u32 trans_len; > +}; > + > #define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0) > #define KVM_DEV_ASSIGN_PCI_2_3 (1 << 1) > #define KVM_DEV_ASSIGN_MASK_INTX (1 << 2) Reviewed-by: Krish Sadhukhan