From patchwork Thu Feb 24 17:25:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Raghavendra Rao Ananta X-Patchwork-Id: 12759067 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 831BAC433F5 for ; Thu, 24 Feb 2022 17:26:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231808AbiBXR1Z (ORCPT ); Thu, 24 Feb 2022 12:27:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41300 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231807AbiBXR1M (ORCPT ); Thu, 24 Feb 2022 12:27:12 -0500 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 85E2032071 for ; Thu, 24 Feb 2022 09:26:33 -0800 (PST) Received: by mail-pl1-x649.google.com with SMTP id p5-20020a170902bd0500b00148cb2d29ecso1419439pls.4 for ; Thu, 24 Feb 2022 09:26:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=KxLF7qzKbc8UFtk7tO6zSgT4pjqe2yY92U69kuJWElE=; b=Ibq2L/kDegT2ECNcaQXPAs7djEODMNl6Odaya6jgnPWZwo8ddlFwZQf5S2DV1lDKXh KvqDVlQRjlXs0r+9hv5s4YACXuw+mZH8LtJ9PjnUl+m/ZKgOJhNu5UTG/sW92wXtuJ53 uTA70vfKFeeqKKcz3kmCuUJDCYC2jsj1x3VKD3fMxhwpYqXFxkE6Ryi/kYomzSshDYFb zaCFurXQqXvGlWD9SuSkzApAxF7z4m7vGgt6OanmwFR3UcAlwoV4m/vf2Dl/KySQsaX/ ID6OoI+rC9i9ZACeBS2AWlYwc3JMYgiMB0VLfj+e4bNJ3K/2wDtWal25WRCbJUUBRdW1 09hA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=KxLF7qzKbc8UFtk7tO6zSgT4pjqe2yY92U69kuJWElE=; b=eGaMiTpkxPIjKQ7JKk73ansQjQgasJ7JfRB2dxGXlPO7kHZsl2KH7SVMRAedsfGa5r VbVsgyhsF4t0gCQ825C+X5LG4JIB+E/XYVSF5cxfE9onO+eYYHbBbm9f0gnxQVf+E7/N 3rqPofWf/ukHwmWV/eTbXgKwFHep8JYLzCAwH0cbEugH0JOtNFORbiH6ZtgCZ15lIJQE 6lX3cCZSJg5GzJSUf3jdtnybh6ghKFgDPRGVG1M9c5PWQuFPKHcMuLc5CnjqAHeU9qDu 3alHCy84MFEHxarE7ZOr+kk3hbHgjyj5TUY8hbM3/YrpFg/IwChQm39RSTQ6yjLNgx3e 37VQ== X-Gm-Message-State: AOAM5304vzUajMCD31r8xkvWrwHj+3vB+hil6geUq7rPOD7EDdCUCSwu 8HEMAum6SAWyeY5v/vNWvK+VPH4Kyy6y X-Google-Smtp-Source: ABdhPJyrVMqrzObbtdrqsKfy7PVH706+lroyD/W5B1nltv6iTYOALVQlwfiPpkDn123mnsFrgGkxxJ5C3gkx X-Received: from rananta-virt.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:1bcc]) (user=rananta job=sendgmr) by 2002:a17:902:d345:b0:14f:ee29:5ee6 with SMTP id l5-20020a170902d34500b0014fee295ee6mr3440637plk.102.1645723593017; Thu, 24 Feb 2022 09:26:33 -0800 (PST) Date: Thu, 24 Feb 2022 17:25:57 +0000 In-Reply-To: <20220224172559.4170192-1-rananta@google.com> Message-Id: <20220224172559.4170192-12-rananta@google.com> Mime-Version: 1.0 References: <20220224172559.4170192-1-rananta@google.com> X-Mailer: git-send-email 2.35.1.574.g5d30c73bfb-goog Subject: [PATCH v4 11/13] selftests: KVM: aarch64: Introduce hypercall ABI test From: Raghavendra Rao Ananta To: Marc Zyngier , Andrew Jones , James Morse , Alexandru Elisei , Suzuki K Poulose Cc: Paolo Bonzini , Catalin Marinas , Will Deacon , Peter Shier , Ricardo Koller , Oliver Upton , Reiji Watanabe , Jing Zhang , Raghavendra Rao Anata , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Introduce a KVM selftest to check the hypercall interface for arm64 platforms. The test validates the user-space's IOCTL interface to read/write the psuedo-firmware registers as well as its effects on the guest upon certain configurations. Signed-off-by: Raghavendra Rao Ananta --- tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/aarch64/hypercalls.c | 376 ++++++++++++++++++ 3 files changed, 378 insertions(+) create mode 100644 tools/testing/selftests/kvm/aarch64/hypercalls.c diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore index ac69108d9ffd..f13c33fcd733 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -2,6 +2,7 @@ /aarch64/arch_timer /aarch64/debug-exceptions /aarch64/get-reg-list +/aarch64/hypercalls /aarch64/psci_test /aarch64/vgic_init /aarch64/vgic_irq diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 2a27c09b22ae..2181bdd5b09c 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -102,6 +102,7 @@ TEST_GEN_PROGS_x86_64 += system_counter_offset_test TEST_GEN_PROGS_aarch64 += aarch64/arch_timer TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list +TEST_GEN_PROGS_aarch64 += aarch64/hypercalls TEST_GEN_PROGS_aarch64 += aarch64/psci_test TEST_GEN_PROGS_aarch64 += aarch64/vgic_init TEST_GEN_PROGS_aarch64 += aarch64/vgic_irq diff --git a/tools/testing/selftests/kvm/aarch64/hypercalls.c b/tools/testing/selftests/kvm/aarch64/hypercalls.c new file mode 100644 index 000000000000..e4e3a286ff3e --- /dev/null +++ b/tools/testing/selftests/kvm/aarch64/hypercalls.c @@ -0,0 +1,376 @@ +// SPDX-License-Identifier: GPL-2.0-only + +/* hypercalls: Check the ARM64's psuedo-firmware bitmap register interface. + * + * The test validates the basic hypercall functionalities that are exposed + * via the psuedo-firmware bitmap register. This includes the registers' + * read/write behavior before and after the VM has started, and if the + * hypercalls are properly masked or unmasked to the guest when disabled or + * enabled from the KVM userspace, respectively. + */ + +#include +#include +#include +#include + +#include "processor.h" + +#define FW_REG_ULIMIT_VAL(max_feat_bit) (GENMASK_ULL(max_feat_bit, 0)) + +struct kvm_fw_reg_info { + uint64_t reg; /* Register definition */ + uint64_t max_feat_bit; /* Bit that represents the upper limit of the feature-map */ +}; + +#define FW_REG_INFO(r, bit_max) \ + { \ + .reg = r, \ + .max_feat_bit = bit_max, \ + } + +static const struct kvm_fw_reg_info fw_reg_info[] = { + FW_REG_INFO(KVM_REG_ARM_STD_BMAP, KVM_REG_ARM_STD_BMAP_BIT_MAX), + FW_REG_INFO(KVM_REG_ARM_STD_HYP_BMAP, KVM_REG_ARM_STD_HYP_BMAP_BIT_MAX), + FW_REG_INFO(KVM_REG_ARM_VENDOR_HYP_BMAP, KVM_REG_ARM_VENDOR_HYP_BMAP_BIT_MAX), +}; + +enum test_stage { + TEST_STAGE_REG_IFACE, + TEST_STAGE_HVC_IFACE_FEAT_DISABLED, + TEST_STAGE_HVC_IFACE_FEAT_ENABLED, + TEST_STAGE_HVC_IFACE_FALSE_INFO, + TEST_STAGE_END, +}; + +static int stage; + +struct test_hvc_info { + uint32_t func_id; + int64_t arg0; + + void (*test_hvc_disabled)(const struct test_hvc_info *hc_info, + struct arm_smccc_res *res); + void (*test_hvc_enabled)(const struct test_hvc_info *hc_info, + struct arm_smccc_res *res); +}; + +#define TEST_HVC_INFO(f, a0, test_disabled, test_enabled) \ + { \ + .func_id = f, \ + .arg0 = a0, \ + .test_hvc_disabled = test_disabled, \ + .test_hvc_enabled = test_enabled, \ + } + +static void +test_ptp_feat_hvc_disabled(const struct test_hvc_info *hc_info, struct arm_smccc_res *res) +{ + GUEST_ASSERT_3((res->a0 & BIT(ARM_SMCCC_KVM_FUNC_PTP)) == 0, + res->a0, hc_info->func_id, hc_info->arg0); +} + +static void +test_ptp_feat_hvc_enabled(const struct test_hvc_info *hc_info, struct arm_smccc_res *res) +{ + GUEST_ASSERT_3((res->a0 & BIT(ARM_SMCCC_KVM_FUNC_PTP)) != 0, + res->a0, hc_info->func_id, hc_info->arg0); +} + +static const struct test_hvc_info hvc_info[] = { + /* KVM_REG_ARM_STD_BMAP: KVM_REG_ARM_STD_BIT_TRNG_V1_0 */ + TEST_HVC_INFO(ARM_SMCCC_TRNG_VERSION, 0, NULL, NULL), + TEST_HVC_INFO(ARM_SMCCC_TRNG_FEATURES, ARM_SMCCC_TRNG_RND64, NULL, NULL), + TEST_HVC_INFO(ARM_SMCCC_TRNG_GET_UUID, 0, NULL, NULL), + TEST_HVC_INFO(ARM_SMCCC_TRNG_RND32, 0, NULL, NULL), + TEST_HVC_INFO(ARM_SMCCC_TRNG_RND64, 0, NULL, NULL), + + /* KVM_REG_ARM_STD_HYP_BMAP: KVM_REG_ARM_STD_HYP_BIT_PV_TIME */ + TEST_HVC_INFO(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_HV_PV_TIME_FEATURES, NULL, NULL), + TEST_HVC_INFO(ARM_SMCCC_HV_PV_TIME_FEATURES, + ARM_SMCCC_HV_PV_TIME_ST, NULL, NULL), + TEST_HVC_INFO(ARM_SMCCC_HV_PV_TIME_ST, 0, NULL, NULL), + + /* KVM_REG_ARM_VENDOR_HYP_BMAP: KVM_REG_ARM_VENDOR_HYP_BIT_PTP */ + TEST_HVC_INFO(ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID, + ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID, + test_ptp_feat_hvc_disabled, test_ptp_feat_hvc_enabled), + TEST_HVC_INFO(ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID, + KVM_PTP_VIRT_COUNTER, NULL, NULL), +}; + +/* Feed false hypercall info to test the KVM behavior */ +static const struct test_hvc_info false_hvc_info[] = { + /* Feature support check against a different family of hypercalls */ + TEST_HVC_INFO(ARM_SMCCC_TRNG_FEATURES, + ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID, NULL, NULL), + TEST_HVC_INFO(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_TRNG_RND64, NULL, NULL), + TEST_HVC_INFO(ARM_SMCCC_HV_PV_TIME_FEATURES, + ARM_SMCCC_TRNG_RND64, NULL, NULL), +}; + +static void guest_test_hvc(const struct test_hvc_info *hc_info) +{ + unsigned int i; + struct arm_smccc_res res; + unsigned int hvc_info_arr_sz; + + hvc_info_arr_sz = + hc_info == hvc_info ? ARRAY_SIZE(hvc_info) : ARRAY_SIZE(false_hvc_info); + + for (i = 0; i < hvc_info_arr_sz; i++, hc_info++) { + + memset(&res, 0, sizeof(res)); + smccc_hvc(hc_info->func_id, hc_info->arg0, 0, 0, 0, 0, 0, 0, &res); + + switch (stage) { + case TEST_STAGE_HVC_IFACE_FEAT_DISABLED: + if (hc_info->test_hvc_disabled) + hc_info->test_hvc_disabled(hc_info, &res); + else + GUEST_ASSERT_3(res.a0 == SMCCC_RET_NOT_SUPPORTED, + res.a0, hc_info->func_id, hc_info->arg0); + break; + case TEST_STAGE_HVC_IFACE_FEAT_ENABLED: + if (hc_info->test_hvc_enabled) + hc_info->test_hvc_enabled(hc_info, &res); + else + GUEST_ASSERT_3(res.a0 != SMCCC_RET_NOT_SUPPORTED, + res.a0, hc_info->func_id, hc_info->arg0); + break; + case TEST_STAGE_HVC_IFACE_FALSE_INFO: + GUEST_ASSERT_3(res.a0 == SMCCC_RET_NOT_SUPPORTED, + res.a0, hc_info->func_id, hc_info->arg0); + break; + default: + GUEST_ASSERT_1(0, stage); + } + } +} + +static void guest_code(void) +{ + while (stage != TEST_STAGE_END) { + switch (stage) { + case TEST_STAGE_REG_IFACE: + break; + case TEST_STAGE_HVC_IFACE_FEAT_DISABLED: + case TEST_STAGE_HVC_IFACE_FEAT_ENABLED: + guest_test_hvc(hvc_info); + break; + case TEST_STAGE_HVC_IFACE_FALSE_INFO: + guest_test_hvc(false_hvc_info); + break; + default: + GUEST_ASSERT_1(0, stage); + } + + GUEST_SYNC(stage); + } + + GUEST_DONE(); +} + +static int set_fw_reg(struct kvm_vm *vm, uint64_t id, uint64_t val) +{ + struct kvm_one_reg reg = { + .id = KVM_REG_ARM_FW_REG(id), + .addr = (uint64_t)&val, + }; + + return _vcpu_ioctl(vm, 0, KVM_SET_ONE_REG, ®); +} + +static void get_fw_reg(struct kvm_vm *vm, uint64_t id, uint64_t *addr) +{ + struct kvm_one_reg reg = { + .id = KVM_REG_ARM_FW_REG(id), + .addr = (uint64_t)addr, + }; + + return vcpu_ioctl(vm, 0, KVM_GET_ONE_REG, ®); +} + +struct st_time { + uint32_t rev; + uint32_t attr; + uint64_t st_time; +}; + +#define STEAL_TIME_SIZE ((sizeof(struct st_time) + 63) & ~63) +#define ST_GPA_BASE (1 << 30) + +static void steal_time_init(struct kvm_vm *vm) +{ + uint64_t st_ipa = (ulong)ST_GPA_BASE; + unsigned int gpages; + struct kvm_device_attr dev = { + .group = KVM_ARM_VCPU_PVTIME_CTRL, + .attr = KVM_ARM_VCPU_PVTIME_IPA, + .addr = (uint64_t)&st_ipa, + }; + + gpages = vm_calc_num_guest_pages(VM_MODE_DEFAULT, STEAL_TIME_SIZE); + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, ST_GPA_BASE, 1, gpages, 0); + + vcpu_ioctl(vm, 0, KVM_SET_DEVICE_ATTR, &dev); +} + +static void test_fw_regs_before_vm_start(struct kvm_vm *vm) +{ + uint64_t val; + unsigned int i; + int ret; + + for (i = 0; i < ARRAY_SIZE(fw_reg_info); i++) { + const struct kvm_fw_reg_info *reg_info = &fw_reg_info[i]; + + /* First read should be an upper limit of the features supported */ + get_fw_reg(vm, reg_info->reg, &val); + TEST_ASSERT(val == FW_REG_ULIMIT_VAL(reg_info->max_feat_bit), + "Expected all the features to be set for reg: 0x%lx; expected: 0x%llx; read: 0x%lx\n", + reg_info->reg, GENMASK_ULL(reg_info->max_feat_bit, 0), val); + + /* Test 'write' by disabling all the features of the register map */ + ret = set_fw_reg(vm, reg_info->reg, 0); + TEST_ASSERT(ret == 0, + "Failed to clear all the features of reg: 0x%lx; ret: %d\n", + reg_info->reg, errno); + + get_fw_reg(vm, reg_info->reg, &val); + TEST_ASSERT(val == 0, + "Expected all the features to be cleared for reg: 0x%lx\n", reg_info->reg); + + /* + * Test enabling a feature that's not supported. + * Avoid this check if all the bits are occupied. + */ + if (reg_info->max_feat_bit < 63) { + ret = set_fw_reg(vm, reg_info->reg, BIT(reg_info->max_feat_bit + 1)); + TEST_ASSERT(ret != 0 && errno == EINVAL, + "Unexpected behavior or return value (%d) while setting an unsupported feature for reg: 0x%lx\n", + errno, reg_info->reg); + } + } +} + +static void test_fw_regs_after_vm_start(struct kvm_vm *vm) +{ + uint64_t val; + unsigned int i; + int ret; + + for (i = 0; i < ARRAY_SIZE(fw_reg_info); i++) { + const struct kvm_fw_reg_info *reg_info = &fw_reg_info[i]; + + /* + * Before starting the VM, the test clears all the bits. + * Check if that's still the case. + */ + get_fw_reg(vm, reg_info->reg, &val); + TEST_ASSERT(val == 0, + "Expected all the features to be cleared for reg: 0x%lx\n", + reg_info->reg); + + /* + * Test setting the last read value. KVM should allow this + * even if VM has started running. + */ + ret = set_fw_reg(vm, reg_info->reg, val); + TEST_ASSERT(ret == 0, + "Failed to set the register with previously read value after Vm start for reg: 0x%lx; ret: %d\n", + reg_info->reg, errno); + + /* + * Set all the features for this register again. KVM shouldn't + * allow this as the VM is running. + */ + ret = set_fw_reg(vm, reg_info->reg, FW_REG_ULIMIT_VAL(reg_info->max_feat_bit)); + TEST_ASSERT(ret != 0 && errno == EBUSY, + "Unexpected behavior or return value (%d) while setting a feature while VM is running for reg: 0x%lx\n", + errno, reg_info->reg); + } +} + +static struct kvm_vm *test_vm_create(void) +{ + struct kvm_vm *vm; + + vm = vm_create_default(0, 0, guest_code); + + ucall_init(vm, NULL); + steal_time_init(vm); + + return vm; +} + +static struct kvm_vm *test_guest_stage(struct kvm_vm *vm) +{ + struct kvm_vm *ret_vm = vm; + + pr_debug("Stage: %d\n", stage); + + switch (stage) { + case TEST_STAGE_REG_IFACE: + test_fw_regs_after_vm_start(vm); + break; + case TEST_STAGE_HVC_IFACE_FEAT_DISABLED: + /* Start a new VM so that all the features are now enabled by default */ + kvm_vm_free(vm); + ret_vm = test_vm_create(); + break; + case TEST_STAGE_HVC_IFACE_FEAT_ENABLED: + case TEST_STAGE_HVC_IFACE_FALSE_INFO: + break; + default: + TEST_FAIL("Unknown test stage: %d\n", stage); + } + + stage++; + sync_global_to_guest(vm, stage); + + return ret_vm; +} + +static void test_run(void) +{ + struct kvm_vm *vm; + struct ucall uc; + bool guest_done = false; + + vm = test_vm_create(); + + test_fw_regs_before_vm_start(vm); + + while (!guest_done) { + vcpu_run(vm, 0); + + switch (get_ucall(vm, 0, &uc)) { + case UCALL_SYNC: + vm = test_guest_stage(vm); + break; + case UCALL_DONE: + guest_done = true; + break; + case UCALL_ABORT: + TEST_FAIL("%s at %s:%ld\n\tvalues: 0x%lx, 0x%lx; 0x%lx, stage: %u", + (const char *)uc.args[0], __FILE__, uc.args[1], + uc.args[2], uc.args[3], uc.args[4], stage); + break; + default: + TEST_FAIL("Unexpected guest exit\n"); + } + } + + kvm_vm_free(vm); +} + +int main(void) +{ + setbuf(stdout, NULL); + + test_run(); + return 0; +}