From patchwork Mon Aug 29 17:10:19 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Gonda X-Patchwork-Id: 12958267 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6105EC6FA69 for ; Mon, 29 Aug 2022 17:11:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231491AbiH2RLf (ORCPT ); Mon, 29 Aug 2022 13:11:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52856 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231441AbiH2RL0 (ORCPT ); Mon, 29 Aug 2022 13:11:26 -0400 Received: from mail-pl1-x649.google.com (mail-pl1-x649.google.com [IPv6:2607:f8b0:4864:20::649]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 75BF361DB3 for ; Mon, 29 Aug 2022 10:11:02 -0700 (PDT) Received: by mail-pl1-x649.google.com with SMTP id h12-20020a170902f54c00b0016f8858ce9bso6467088plf.9 for ; Mon, 29 Aug 2022 10:11:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:from:to:cc; bh=qYBu9gvtSH25gzhu9AMMMrhFUrc6l+KYBGnqODMY8CI=; b=VQ/GS+WrbwpQxbs7uP6/1uuMKIc8Qp7pagAU63kllL+2+jGmpPYU0tO5ogwGOPfrHm vDgXW3vMtbWgrzSzPlj3qKA2pJba7bFL+cCmPx7jwKT8kh468FHjO8lo9NnHkwRAehy5 Gn09ia2P7x4qjIRMNX86MyqBE7JEzHKuo73sfk9LzpPjzTlgNz0Qprp6tAcS8MRNdw1A J2NVgCKx1aWrPIPWBD/g/46y3eRPCz5J/zvgcyDRj0suGWiedUZLv09rzsxFXJS4/TOj MDt9sLgR85Jc3PfuleG58xhMIgEPurZbAsqMjhFYc0iI8ntbW08plqjDPbCwIL2F8qZJ EJSg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:x-gm-message-state:from:to:cc; bh=qYBu9gvtSH25gzhu9AMMMrhFUrc6l+KYBGnqODMY8CI=; b=xIoLluqmuq1LRGOKdTruaqIrQksuk8pbLFjqH7ojQR173ZjKKbVZXYDq0kI1E5qDbk lzrBwr/bv/2XllA+c06KWCOtRJ9Vu/H96zTDBhSikQ7rvL3qeF3frX977T8a/mW/Q7u+ e31pQhrFn9LzhA17GlwPO71yHOJf58GZubX0pT///tZL+LYK0vRvs8Jm1zw7Iq4EQF8f Ff8zgdeMvMrnvkn79pSV4A3J7Ebs06FTGcGNhu4HZox/nr1eLBNrDZA95Ca3k4GD945j gN3xnm8GsAe5nhNEiEcZJ952nhQ1VzLLeB63sIuNcQJ7BYELx/JyxqOU6vkAT2AQZeEb QL2A== X-Gm-Message-State: ACgBeo3IipzPP1PQr15Hw+K+MtLGQrrD/LvqwKhT2VTXH9dHDIi8kpSo POsvyzlrMAnvUZtZpDBKzgmLVxkVq4MaeAbn0ptZuHAVFpS4k68USWq7M1IK0vRkqhnwfAzJmh7 pWpC9qMV3oh1LM5MEQhgDLoSGZEejzZcYAbACOngpyT0umb7+lptagyMkeA== X-Google-Smtp-Source: AA6agR7GBGZ5S1BuVQpRcvhwV3Zq/amjMJEM/KN6XPoeQKwtvyCOh5BKqVStNRP9yUi0i3hZOjPsANV5J3k= X-Received: from pgonda1.kir.corp.google.com ([2620:15c:29:203:cddb:77a7:c55e:a7a2]) (user=pgonda job=sendgmr) by 2002:a17:902:be02:b0:172:d409:e057 with SMTP id r2-20020a170902be0200b00172d409e057mr17472215pls.90.1661793061692; Mon, 29 Aug 2022 10:11:01 -0700 (PDT) Date: Mon, 29 Aug 2022 10:10:19 -0700 In-Reply-To: <20220829171021.701198-1-pgonda@google.com> Message-Id: <20220829171021.701198-7-pgonda@google.com> Mime-Version: 1.0 References: <20220829171021.701198-1-pgonda@google.com> X-Mailer: git-send-email 2.37.2.672.g94769d06f0-goog Subject: [V4 6/8] KVM: selftests: add library for creating/interacting with SEV guests From: Peter Gonda To: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org, marcorr@google.com, seanjc@google.com, michael.roth@amd.com, thomas.lendacky@amd.com, joro@8bytes.org, mizhang@google.com, pbonzini@redhat.com, andrew.jones@linux.dev, Peter Gonda Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Add interfaces to allow tests to create/manage SEV guests. The additional state associated with these guests is encapsulated in a new struct sev_vm, which is a light wrapper around struct kvm_vm. These VMs will use vm_set_memory_encryption() and vm_get_encrypted_phy_pages() under the covers to configure and sync up with the core kvm_util library on what should/shouldn't be treated as encrypted memory. Originally-by: Michael Roth Signed-off-by: Peter Gonda --- tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/include/kvm_util_base.h | 3 + .../selftests/kvm/include/x86_64/sev.h | 47 ++++ tools/testing/selftests/kvm/lib/x86_64/sev.c | 232 ++++++++++++++++++ 4 files changed, 283 insertions(+) create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev.h create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev.c diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 23649c5d42fc..0a70e50f0498 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -56,6 +56,7 @@ LIBKVM_x86_64 += lib/x86_64/processor.c LIBKVM_x86_64 += lib/x86_64/svm.c LIBKVM_x86_64 += lib/x86_64/ucall.c LIBKVM_x86_64 += lib/x86_64/vmx.c +LIBKVM_x86_64 += lib/x86_64/sev.c LIBKVM_aarch64 += lib/aarch64/gic.c LIBKVM_aarch64 += lib/aarch64/gic_v3.c diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h index 489e8c833e5f..0927e262623d 100644 --- a/tools/testing/selftests/kvm/include/kvm_util_base.h +++ b/tools/testing/selftests/kvm/include/kvm_util_base.h @@ -69,6 +69,7 @@ struct userspace_mem_regions { /* Memory encryption policy/configuration. */ struct vm_memcrypt { bool enabled; + bool encrypted; int8_t enc_by_default; bool has_enc_bit; int8_t enc_bit; @@ -831,6 +832,8 @@ vm_paddr_t addr_arch_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva); static inline vm_paddr_t addr_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva) { + TEST_ASSERT(!vm->memcrypt.encrypted, + "Encrypted guests have their page tables encrypted so gva2gpa conversions are not possible."); return addr_arch_gva2gpa(vm, gva); } diff --git a/tools/testing/selftests/kvm/include/x86_64/sev.h b/tools/testing/selftests/kvm/include/x86_64/sev.h new file mode 100644 index 000000000000..810d36377e8c --- /dev/null +++ b/tools/testing/selftests/kvm/include/x86_64/sev.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Helpers used for SEV guests + * + * Copyright (C) 2021 Advanced Micro Devices + */ +#ifndef SELFTEST_KVM_SEV_H +#define SELFTEST_KVM_SEV_H + +#include +#include +#include "kvm_util.h" + +/* Makefile might set this separately for user-overrides */ +#ifndef SEV_DEV_PATH +#define SEV_DEV_PATH "/dev/sev" +#endif + +#define SEV_FW_REQ_VER_MAJOR 0 +#define SEV_FW_REQ_VER_MINOR 17 + +#define SEV_POLICY_NO_DBG (1UL << 0) +#define SEV_POLICY_ES (1UL << 2) + +enum sev_guest_state { + SEV_GSTATE_UNINIT = 0, + SEV_GSTATE_LUPDATE, + SEV_GSTATE_LSECRET, + SEV_GSTATE_RUNNING, +}; + +struct sev_vm { + struct kvm_vm *vm; + int fd; + int enc_bit; + uint32_t sev_policy; +}; + +void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data); + +struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages); +void sev_vm_free(struct sev_vm *sev); +void sev_vm_launch(struct sev_vm *sev); +void sev_vm_launch_measure(struct sev_vm *sev, uint8_t *measurement); +void sev_vm_launch_finish(struct sev_vm *sev); + +#endif /* SELFTEST_KVM_SEV_H */ diff --git a/tools/testing/selftests/kvm/lib/x86_64/sev.c b/tools/testing/selftests/kvm/lib/x86_64/sev.c new file mode 100644 index 000000000000..dd8d708fd01a --- /dev/null +++ b/tools/testing/selftests/kvm/lib/x86_64/sev.c @@ -0,0 +1,232 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Helpers used for SEV guests + * + * Copyright (C) 2021 Advanced Micro Devices + */ + +#include +#include +#include "kvm_util.h" +#include "linux/psp-sev.h" +#include "processor.h" +#include "sev.h" + +#define CPUID_MEM_ENC_LEAF 0x8000001f +#define CPUID_EBX_CBIT_MASK 0x3f + +/* Common SEV helpers/accessors. */ + +void sev_ioctl(int sev_fd, int cmd, void *data) +{ + int ret; + struct sev_issue_cmd arg; + + arg.cmd = cmd; + arg.data = (unsigned long)data; + ret = ioctl(sev_fd, SEV_ISSUE_CMD, &arg); + TEST_ASSERT(ret == 0, + "SEV ioctl %d failed, error: %d, fw_error: %d", + cmd, ret, arg.error); +} + +void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data) +{ + struct kvm_sev_cmd arg = {0}; + int ret; + + arg.id = cmd; + arg.sev_fd = sev->fd; + arg.data = (__u64)data; + + ret = ioctl(sev->vm->fd, KVM_MEMORY_ENCRYPT_OP, &arg); + TEST_ASSERT(ret == 0, + "SEV KVM ioctl %d failed, rc: %i errno: %i (%s), fw_error: %d", + cmd, ret, errno, strerror(errno), arg.error); +} + +/* Local helpers. */ + +static void sev_register_user_region(struct sev_vm *sev, void *hva, uint64_t size) +{ + struct kvm_enc_region range = {0}; + int ret; + + pr_debug("%s: hva: %p, size: %lu\n", __func__, hva, size); + + range.addr = (__u64)hva; + range.size = size; + + ret = ioctl(sev->vm->fd, KVM_MEMORY_ENCRYPT_REG_REGION, &range); + TEST_ASSERT(ret == 0, "failed to register user range, errno: %i\n", errno); +} + +static void sev_encrypt_phy_range(struct sev_vm *sev, vm_paddr_t gpa, uint64_t size) +{ + struct kvm_sev_launch_update_data ksev_update_data = {0}; + + pr_debug("%s: addr: 0x%lx, size: %lu\n", __func__, gpa, size); + + ksev_update_data.uaddr = (__u64)addr_gpa2hva(sev->vm, gpa); + ksev_update_data.len = size; + + kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_UPDATE_DATA, &ksev_update_data); +} + +static void sev_encrypt(struct sev_vm *sev) +{ + const struct sparsebit *enc_phy_pages; + struct kvm_vm *vm = sev->vm; + sparsebit_idx_t pg = 0; + vm_paddr_t gpa_start; + uint64_t memory_size; + int ctr; + struct userspace_mem_region *region; + + hash_for_each(vm->regions.slot_hash, ctr, region, slot_node) { + enc_phy_pages = vm_get_encrypted_phy_pages( + sev->vm, region->region.slot, &gpa_start, &memory_size); + TEST_ASSERT(enc_phy_pages, + "Unable to retrieve encrypted pages bitmap"); + while (pg < (memory_size / vm->page_size)) { + sparsebit_idx_t pg_cnt; + + if (sparsebit_is_clear(enc_phy_pages, pg)) { + pg = sparsebit_next_set(enc_phy_pages, pg); + if (!pg) + break; + } + + pg_cnt = sparsebit_next_clear(enc_phy_pages, pg) - pg; + if (pg_cnt <= 0) + pg_cnt = 1; + + sev_encrypt_phy_range(sev, + gpa_start + pg * vm->page_size, + pg_cnt * vm->page_size); + pg += pg_cnt; + } + } + + sev->vm->memcrypt.encrypted = true; +} + +/* SEV VM implementation. */ + +static struct sev_vm *sev_vm_alloc(struct kvm_vm *vm) +{ + struct sev_user_data_status sev_status; + uint32_t eax, ebx, ecx, edx; + struct sev_vm *sev; + int sev_fd; + + sev_fd = open(SEV_DEV_PATH, O_RDWR); + if (sev_fd < 0) { + pr_info("Failed to open SEV device, path: %s, error: %d, skipping test.\n", + SEV_DEV_PATH, sev_fd); + return NULL; + } + + sev_ioctl(sev_fd, SEV_PLATFORM_STATUS, &sev_status); + + if (!(sev_status.api_major > SEV_FW_REQ_VER_MAJOR || + (sev_status.api_major == SEV_FW_REQ_VER_MAJOR && + sev_status.api_minor >= SEV_FW_REQ_VER_MINOR))) { + pr_info("SEV FW version too old. Have API %d.%d (build: %d), need %d.%d, skipping test.\n", + sev_status.api_major, sev_status.api_minor, sev_status.build, + SEV_FW_REQ_VER_MAJOR, SEV_FW_REQ_VER_MINOR); + return NULL; + } + + sev = calloc(1, sizeof(*sev)); + sev->fd = sev_fd; + sev->vm = vm; + + /* Get encryption bit via CPUID. */ + cpuid(CPUID_MEM_ENC_LEAF, &eax, &ebx, &ecx, &edx); + sev->enc_bit = ebx & CPUID_EBX_CBIT_MASK; + + return sev; +} + +void sev_vm_free(struct sev_vm *sev) +{ + kvm_vm_free(sev->vm); + close(sev->fd); + free(sev); +} + +struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages) +{ + struct sev_vm *sev; + struct kvm_vm *vm; + + /* Need to handle memslots after init, and after setting memcrypt. */ + vm = vm_create_barebones(); + sev = sev_vm_alloc(vm); + if (!sev) + return NULL; + sev->sev_policy = policy; + + kvm_sev_ioctl(sev, KVM_SEV_INIT, NULL); + + vm->vpages_mapped = sparsebit_alloc(); + vm_set_memory_encryption(vm, true, true, sev->enc_bit); + pr_info("SEV cbit: %d\n", sev->enc_bit); + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, npages, 0); + sev_register_user_region(sev, addr_gpa2hva(vm, 0), + npages * vm->page_size); + + pr_info("SEV guest created, policy: 0x%x, size: %lu KB\n", + sev->sev_policy, npages * vm->page_size / 1024); + + return sev; +} + +void sev_vm_launch(struct sev_vm *sev) +{ + struct kvm_sev_launch_start ksev_launch_start = {0}; + struct kvm_sev_guest_status ksev_status; + + ksev_launch_start.policy = sev->sev_policy; + kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_START, &ksev_launch_start); + kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status); + TEST_ASSERT(ksev_status.policy == sev->sev_policy, "Incorrect guest policy."); + TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE, + "Unexpected guest state: %d", ksev_status.state); + + ucall_init(sev->vm, 0); + + sev_encrypt(sev); +} + +void sev_vm_launch_measure(struct sev_vm *sev, uint8_t *measurement) +{ + struct kvm_sev_launch_measure ksev_launch_measure; + struct kvm_sev_guest_status ksev_guest_status; + + ksev_launch_measure.len = 256; + ksev_launch_measure.uaddr = (__u64)measurement; + kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_MEASURE, &ksev_launch_measure); + + /* Measurement causes a state transition, check that. */ + kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_guest_status); + TEST_ASSERT(ksev_guest_status.state == SEV_GSTATE_LSECRET, + "Unexpected guest state: %d", ksev_guest_status.state); +} + +void sev_vm_launch_finish(struct sev_vm *sev) +{ + struct kvm_sev_guest_status ksev_status; + + kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status); + TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE || + ksev_status.state == SEV_GSTATE_LSECRET, + "Unexpected guest state: %d", ksev_status.state); + + kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_FINISH, NULL); + + kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status); + TEST_ASSERT(ksev_status.state == SEV_GSTATE_RUNNING, + "Unexpected guest state: %d", ksev_status.state); +}