From patchwork Thu Apr 7 01:16:03 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: 12804309 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 00E65C433FE for ; Thu, 7 Apr 2022 01:40:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:From:Subject:References: Mime-Version:Message-Id:In-Reply-To:Date:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=S/PSYod5E0dkLJEApEPuddWZEVVZwoiSCD6rJZWEvOs=; b=YkjjQxY0R8SnYvpFPBoIdPqml5 whBzCRISnbMbmjsQTEXEbAFmywYQ4HhABcNbHE0yrJQi2Z0EOWZkVVaESiCYsnPtguplsTO6Qbiik X84CoJiyvVtFmBBqn2INFqdh3akN5xaFewfj49wR8ySuq0rFa05ziqbhzcFb4B2Y2X0eAdqe0CxHa w1CLvEtGuN/f9DeBloqJCmAnCnzRgO5A47cXApdsbZ/jNCU3jsM/4md53wWboCSN4nK7dkjQFGpcP wN1YHDN2Gwl/Hk+zIScdFdkpd/kfDLdIHJUxpzxLsy/JrsnRTiW21TIOL3C99c1mzWiWUrxjF4t82 51MZLwcg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ncH7D-008hF6-QW; Thu, 07 Apr 2022 01:39:16 +0000 Received: from mail-pf1-x449.google.com ([2607:f8b0:4864:20::449]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ncGlB-008XF7-1r for linux-arm-kernel@lists.infradead.org; Thu, 07 Apr 2022 01:16:32 +0000 Received: by mail-pf1-x449.google.com with SMTP id u18-20020aa78492000000b004fe401db6fbso2466093pfn.4 for ; Wed, 06 Apr 2022 18:16:27 -0700 (PDT) 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=l3viB90yILfzGyCVfXDHThQ+KPiuiXklvJkP4x9pJx8=; b=pMX0GWqtnv0xtofv/q5viC56tCyctBbnFhkFfKPfyZRXMgf3P8Nc0tHvCisnJmHjix EE5zgdWJ0lEhEclvd6YhQvUzxCVpTNZmXtHZoBBSY9fVdIJ3uthhn/S7UuwZfhZrnp0h AYFexL6rtHGiUGZoy/armD9SB06463Av0ouiECQd8Sup69W6rh5mA6UW4KpT15jGPxO7 jcp01KmRIhGoza5Ct2mR/7a6ncRK0F4rCsr9qTsjlTuECu4BO6u0jJtHs1Dal49z5rIX J4c+o2QBVTirENC2Cv32zqh9LbiMSw+drfAc49BSrJMxULegTVTZdgfB+W0KnX1R2ShZ k6BA== 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=l3viB90yILfzGyCVfXDHThQ+KPiuiXklvJkP4x9pJx8=; b=QWW6ywabl1VZJtj8YeOsbTVifJ+LhjXRhvPkwJnOqCSz+/HyMt9czbuky4yux1JQ3I hR/MlLoU9791YYpnyg7AXNO0HlGvzAqUGPKnHmDwGgFCVrDq0kjygZPFichqz91qY1aA iXf3+UcYmy87Rqy7NpcCXkSZTHW/PnPJOwSo6nPnfUmcpMjs40DBpGjS6z2Y2dh1up/K 1fpggI8Yp/uCcbgjCXc1GGz2hcxnl4ENZnbLY2+w9UJN0EeXxzy2CLlrYLvdBWrL0GEA WBqPzGHBkdvbbns31pu67SAX3Zb4sd6C9otxeSqVH1byantHCrX7iMVzzCne2RMFsnWt wubQ== X-Gm-Message-State: AOAM532+iCJfndTh0W3RVIZQeaqdIhP8pUKqNhqR4v5fYGxu/wrWJbLy zlt6gFjefSJnDd+q68E1ILBopD7Enzhu X-Google-Smtp-Source: ABdhPJwuIzuQaJvJEs4YysK7AXeOeG1uy1Q0LbJveojJNRwQ8i2y/f3Se1x0b/TJshG29bDRh0vnbxanNGsX X-Received: from rananta-virt.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:1bcc]) (user=rananta job=sendgmr) by 2002:a63:fb44:0:b0:372:9ec8:745a with SMTP id w4-20020a63fb44000000b003729ec8745amr9224643pgj.551.1649294186534; Wed, 06 Apr 2022 18:16:26 -0700 (PDT) Date: Thu, 7 Apr 2022 01:16:03 +0000 In-Reply-To: <20220407011605.1966778-1-rananta@google.com> Message-Id: <20220407011605.1966778-9-rananta@google.com> Mime-Version: 1.0 References: <20220407011605.1966778-1-rananta@google.com> X-Mailer: git-send-email 2.35.1.1094.g7c7d902a7c-goog Subject: [PATCH v5 08/10] 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220406_181629_182042_35566243 X-CRM114-Status: GOOD ( 24.21 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.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 | 344 ++++++++++++++++++ 3 files changed, 346 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 e82b816a6608..7ef52b3b1560 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 2f74f502de65..af4cb88bcf83 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -105,6 +105,7 @@ 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..9941fb75772a --- /dev/null +++ b/tools/testing/selftests/kvm/aarch64/hypercalls.c @@ -0,0 +1,344 @@ +// 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)) + +/* Last valid bits of the bitmapped firmware registers */ +#define KVM_REG_ARM_STD_BMAP_BIT_MAX 0 +#define KVM_REG_ARM_STD_HYP_BMAP_BIT_MAX 0 +#define KVM_REG_ARM_VENDOR_HYP_BMAP_BIT_MAX 1 + +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; +}; + +#define TEST_HVC_INFO(f, a0) \ + { \ + .func_id = f, \ + .arg0 = a0, \ + } + +static const struct test_hvc_info hvc_info[] = { + /* KVM_REG_ARM_STD_BMAP */ + TEST_HVC_INFO(ARM_SMCCC_TRNG_VERSION, 0), + TEST_HVC_INFO(ARM_SMCCC_TRNG_FEATURES, ARM_SMCCC_TRNG_RND64), + TEST_HVC_INFO(ARM_SMCCC_TRNG_GET_UUID, 0), + TEST_HVC_INFO(ARM_SMCCC_TRNG_RND32, 0), + TEST_HVC_INFO(ARM_SMCCC_TRNG_RND64, 0), + + /* KVM_REG_ARM_STD_HYP_BMAP */ + TEST_HVC_INFO(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, ARM_SMCCC_HV_PV_TIME_FEATURES), + TEST_HVC_INFO(ARM_SMCCC_HV_PV_TIME_FEATURES, ARM_SMCCC_HV_PV_TIME_ST), + TEST_HVC_INFO(ARM_SMCCC_HV_PV_TIME_ST, 0), + + /* KVM_REG_ARM_VENDOR_HYP_BMAP */ + TEST_HVC_INFO(ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID, + ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID), + TEST_HVC_INFO(ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID, KVM_PTP_VIRT_COUNTER), +}; + +/* 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), + TEST_HVC_INFO(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, ARM_SMCCC_TRNG_RND64), + TEST_HVC_INFO(ARM_SMCCC_HV_PV_TIME_FEATURES, ARM_SMCCC_TRNG_RND64), +}; + +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: + 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; + case TEST_STAGE_HVC_IFACE_FEAT_ENABLED: + 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 = 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 = id, + .addr = (uint64_t)addr, + }; + + 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 a '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; +}