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1// SPDX-License-Identifier: GPL-2.0-only2 3/* hypercalls: Check the ARM64's psuedo-firmware bitmap register interface.4 *5 * The test validates the basic hypercall functionalities that are exposed6 * via the psuedo-firmware bitmap register. This includes the registers'7 * read/write behavior before and after the VM has started, and if the8 * hypercalls are properly masked or unmasked to the guest when disabled or9 * enabled from the KVM userspace, respectively.10 */11#include <errno.h>12#include <linux/arm-smccc.h>13#include <asm/kvm.h>14#include <kvm_util.h>15 16#include "processor.h"17 18#define FW_REG_ULIMIT_VAL(max_feat_bit) (GENMASK(max_feat_bit, 0))19 20/* Last valid bits of the bitmapped firmware registers */21#define KVM_REG_ARM_STD_BMAP_BIT_MAX 022#define KVM_REG_ARM_STD_HYP_BMAP_BIT_MAX 023#define KVM_REG_ARM_VENDOR_HYP_BMAP_BIT_MAX 124 25struct kvm_fw_reg_info {26 uint64_t reg; /* Register definition */27 uint64_t max_feat_bit; /* Bit that represents the upper limit of the feature-map */28};29 30#define FW_REG_INFO(r) \31 { \32 .reg = r, \33 .max_feat_bit = r##_BIT_MAX, \34 }35 36static const struct kvm_fw_reg_info fw_reg_info[] = {37 FW_REG_INFO(KVM_REG_ARM_STD_BMAP),38 FW_REG_INFO(KVM_REG_ARM_STD_HYP_BMAP),39 FW_REG_INFO(KVM_REG_ARM_VENDOR_HYP_BMAP),40};41 42enum test_stage {43 TEST_STAGE_REG_IFACE,44 TEST_STAGE_HVC_IFACE_FEAT_DISABLED,45 TEST_STAGE_HVC_IFACE_FEAT_ENABLED,46 TEST_STAGE_HVC_IFACE_FALSE_INFO,47 TEST_STAGE_END,48};49 50static int stage = TEST_STAGE_REG_IFACE;51 52struct test_hvc_info {53 uint32_t func_id;54 uint64_t arg1;55};56 57#define TEST_HVC_INFO(f, a1) \58 { \59 .func_id = f, \60 .arg1 = a1, \61 }62 63static const struct test_hvc_info hvc_info[] = {64 /* KVM_REG_ARM_STD_BMAP */65 TEST_HVC_INFO(ARM_SMCCC_TRNG_VERSION, 0),66 TEST_HVC_INFO(ARM_SMCCC_TRNG_FEATURES, ARM_SMCCC_TRNG_RND64),67 TEST_HVC_INFO(ARM_SMCCC_TRNG_GET_UUID, 0),68 TEST_HVC_INFO(ARM_SMCCC_TRNG_RND32, 0),69 TEST_HVC_INFO(ARM_SMCCC_TRNG_RND64, 0),70 71 /* KVM_REG_ARM_STD_HYP_BMAP */72 TEST_HVC_INFO(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, ARM_SMCCC_HV_PV_TIME_FEATURES),73 TEST_HVC_INFO(ARM_SMCCC_HV_PV_TIME_FEATURES, ARM_SMCCC_HV_PV_TIME_ST),74 TEST_HVC_INFO(ARM_SMCCC_HV_PV_TIME_ST, 0),75 76 /* KVM_REG_ARM_VENDOR_HYP_BMAP */77 TEST_HVC_INFO(ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID,78 ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID),79 TEST_HVC_INFO(ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID, 0),80 TEST_HVC_INFO(ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID, KVM_PTP_VIRT_COUNTER),81};82 83/* Feed false hypercall info to test the KVM behavior */84static const struct test_hvc_info false_hvc_info[] = {85 /* Feature support check against a different family of hypercalls */86 TEST_HVC_INFO(ARM_SMCCC_TRNG_FEATURES, ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID),87 TEST_HVC_INFO(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, ARM_SMCCC_TRNG_RND64),88 TEST_HVC_INFO(ARM_SMCCC_HV_PV_TIME_FEATURES, ARM_SMCCC_TRNG_RND64),89};90 91static void guest_test_hvc(const struct test_hvc_info *hc_info)92{93 unsigned int i;94 struct arm_smccc_res res;95 unsigned int hvc_info_arr_sz;96 97 hvc_info_arr_sz =98 hc_info == hvc_info ? ARRAY_SIZE(hvc_info) : ARRAY_SIZE(false_hvc_info);99 100 for (i = 0; i < hvc_info_arr_sz; i++, hc_info++) {101 memset(&res, 0, sizeof(res));102 smccc_hvc(hc_info->func_id, hc_info->arg1, 0, 0, 0, 0, 0, 0, &res);103 104 switch (stage) {105 case TEST_STAGE_HVC_IFACE_FEAT_DISABLED:106 case TEST_STAGE_HVC_IFACE_FALSE_INFO:107 __GUEST_ASSERT(res.a0 == SMCCC_RET_NOT_SUPPORTED,108 "a0 = 0x%lx, func_id = 0x%x, arg1 = 0x%lx, stage = %u",109 res.a0, hc_info->func_id, hc_info->arg1, stage);110 break;111 case TEST_STAGE_HVC_IFACE_FEAT_ENABLED:112 __GUEST_ASSERT(res.a0 != SMCCC_RET_NOT_SUPPORTED,113 "a0 = 0x%lx, func_id = 0x%x, arg1 = 0x%lx, stage = %u",114 res.a0, hc_info->func_id, hc_info->arg1, stage);115 break;116 default:117 GUEST_FAIL("Unexpected stage = %u", stage);118 }119 }120}121 122static void guest_code(void)123{124 while (stage != TEST_STAGE_END) {125 switch (stage) {126 case TEST_STAGE_REG_IFACE:127 break;128 case TEST_STAGE_HVC_IFACE_FEAT_DISABLED:129 case TEST_STAGE_HVC_IFACE_FEAT_ENABLED:130 guest_test_hvc(hvc_info);131 break;132 case TEST_STAGE_HVC_IFACE_FALSE_INFO:133 guest_test_hvc(false_hvc_info);134 break;135 default:136 GUEST_FAIL("Unexpected stage = %u", stage);137 }138 139 GUEST_SYNC(stage);140 }141 142 GUEST_DONE();143}144 145struct st_time {146 uint32_t rev;147 uint32_t attr;148 uint64_t st_time;149};150 151#define STEAL_TIME_SIZE ((sizeof(struct st_time) + 63) & ~63)152#define ST_GPA_BASE (1 << 30)153 154static void steal_time_init(struct kvm_vcpu *vcpu)155{156 uint64_t st_ipa = (ulong)ST_GPA_BASE;157 unsigned int gpages;158 159 gpages = vm_calc_num_guest_pages(VM_MODE_DEFAULT, STEAL_TIME_SIZE);160 vm_userspace_mem_region_add(vcpu->vm, VM_MEM_SRC_ANONYMOUS, ST_GPA_BASE, 1, gpages, 0);161 162 vcpu_device_attr_set(vcpu, KVM_ARM_VCPU_PVTIME_CTRL,163 KVM_ARM_VCPU_PVTIME_IPA, &st_ipa);164}165 166static void test_fw_regs_before_vm_start(struct kvm_vcpu *vcpu)167{168 uint64_t val;169 unsigned int i;170 int ret;171 172 for (i = 0; i < ARRAY_SIZE(fw_reg_info); i++) {173 const struct kvm_fw_reg_info *reg_info = &fw_reg_info[i];174 175 /* First 'read' should be an upper limit of the features supported */176 vcpu_get_reg(vcpu, reg_info->reg, &val);177 TEST_ASSERT(val == FW_REG_ULIMIT_VAL(reg_info->max_feat_bit),178 "Expected all the features to be set for reg: 0x%lx; expected: 0x%lx; read: 0x%lx",179 reg_info->reg, FW_REG_ULIMIT_VAL(reg_info->max_feat_bit), val);180 181 /* Test a 'write' by disabling all the features of the register map */182 ret = __vcpu_set_reg(vcpu, reg_info->reg, 0);183 TEST_ASSERT(ret == 0,184 "Failed to clear all the features of reg: 0x%lx; ret: %d",185 reg_info->reg, errno);186 187 vcpu_get_reg(vcpu, reg_info->reg, &val);188 TEST_ASSERT(val == 0,189 "Expected all the features to be cleared for reg: 0x%lx", reg_info->reg);190 191 /*192 * Test enabling a feature that's not supported.193 * Avoid this check if all the bits are occupied.194 */195 if (reg_info->max_feat_bit < 63) {196 ret = __vcpu_set_reg(vcpu, reg_info->reg, BIT(reg_info->max_feat_bit + 1));197 TEST_ASSERT(ret != 0 && errno == EINVAL,198 "Unexpected behavior or return value (%d) while setting an unsupported feature for reg: 0x%lx",199 errno, reg_info->reg);200 }201 }202}203 204static void test_fw_regs_after_vm_start(struct kvm_vcpu *vcpu)205{206 uint64_t val;207 unsigned int i;208 int ret;209 210 for (i = 0; i < ARRAY_SIZE(fw_reg_info); i++) {211 const struct kvm_fw_reg_info *reg_info = &fw_reg_info[i];212 213 /*214 * Before starting the VM, the test clears all the bits.215 * Check if that's still the case.216 */217 vcpu_get_reg(vcpu, reg_info->reg, &val);218 TEST_ASSERT(val == 0,219 "Expected all the features to be cleared for reg: 0x%lx",220 reg_info->reg);221 222 /*223 * Since the VM has run at least once, KVM shouldn't allow modification of224 * the registers and should return EBUSY. Set the registers and check for225 * the expected errno.226 */227 ret = __vcpu_set_reg(vcpu, reg_info->reg, FW_REG_ULIMIT_VAL(reg_info->max_feat_bit));228 TEST_ASSERT(ret != 0 && errno == EBUSY,229 "Unexpected behavior or return value (%d) while setting a feature while VM is running for reg: 0x%lx",230 errno, reg_info->reg);231 }232}233 234static struct kvm_vm *test_vm_create(struct kvm_vcpu **vcpu)235{236 struct kvm_vm *vm;237 238 vm = vm_create_with_one_vcpu(vcpu, guest_code);239 240 steal_time_init(*vcpu);241 242 return vm;243}244 245static void test_guest_stage(struct kvm_vm **vm, struct kvm_vcpu **vcpu)246{247 int prev_stage = stage;248 249 pr_debug("Stage: %d\n", prev_stage);250 251 /* Sync the stage early, the VM might be freed below. */252 stage++;253 sync_global_to_guest(*vm, stage);254 255 switch (prev_stage) {256 case TEST_STAGE_REG_IFACE:257 test_fw_regs_after_vm_start(*vcpu);258 break;259 case TEST_STAGE_HVC_IFACE_FEAT_DISABLED:260 /* Start a new VM so that all the features are now enabled by default */261 kvm_vm_free(*vm);262 *vm = test_vm_create(vcpu);263 break;264 case TEST_STAGE_HVC_IFACE_FEAT_ENABLED:265 case TEST_STAGE_HVC_IFACE_FALSE_INFO:266 break;267 default:268 TEST_FAIL("Unknown test stage: %d", prev_stage);269 }270}271 272static void test_run(void)273{274 struct kvm_vcpu *vcpu;275 struct kvm_vm *vm;276 struct ucall uc;277 bool guest_done = false;278 279 vm = test_vm_create(&vcpu);280 281 test_fw_regs_before_vm_start(vcpu);282 283 while (!guest_done) {284 vcpu_run(vcpu);285 286 switch (get_ucall(vcpu, &uc)) {287 case UCALL_SYNC:288 test_guest_stage(&vm, &vcpu);289 break;290 case UCALL_DONE:291 guest_done = true;292 break;293 case UCALL_ABORT:294 REPORT_GUEST_ASSERT(uc);295 break;296 default:297 TEST_FAIL("Unexpected guest exit");298 }299 }300 301 kvm_vm_free(vm);302}303 304int main(void)305{306 test_run();307 return 0;308}309