1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * psci_cpu_on_test - Test that the observable state of a vCPU targeted by the 4 * CPU_ON PSCI call matches what the caller requested. 5 * 6 * Copyright (c) 2021 Google LLC. 7 * 8 * This is a regression test for a race between KVM servicing the PSCI call and 9 * userspace reading the vCPUs registers. 10 */ 11 12 #define _GNU_SOURCE 13 14 #include <linux/psci.h> 15 16 #include "kvm_util.h" 17 #include "processor.h" 18 #include "test_util.h" 19 20 #define VCPU_ID_SOURCE 0 21 #define VCPU_ID_TARGET 1 22 23 #define CPU_ON_ENTRY_ADDR 0xfeedf00dul 24 #define CPU_ON_CONTEXT_ID 0xdeadc0deul 25 26 static uint64_t psci_cpu_on(uint64_t target_cpu, uint64_t entry_addr, 27 uint64_t context_id) 28 { 29 struct arm_smccc_res res; 30 31 smccc_hvc(PSCI_0_2_FN64_CPU_ON, target_cpu, entry_addr, context_id, 32 0, 0, 0, 0, &res); 33 34 return res.a0; 35 } 36 37 static uint64_t psci_affinity_info(uint64_t target_affinity, 38 uint64_t lowest_affinity_level) 39 { 40 struct arm_smccc_res res; 41 42 smccc_hvc(PSCI_0_2_FN64_AFFINITY_INFO, target_affinity, lowest_affinity_level, 43 0, 0, 0, 0, 0, &res); 44 45 return res.a0; 46 } 47 48 static void guest_main(uint64_t target_cpu) 49 { 50 GUEST_ASSERT(!psci_cpu_on(target_cpu, CPU_ON_ENTRY_ADDR, CPU_ON_CONTEXT_ID)); 51 uint64_t target_state; 52 53 do { 54 target_state = psci_affinity_info(target_cpu, 0); 55 56 GUEST_ASSERT((target_state == PSCI_0_2_AFFINITY_LEVEL_ON) || 57 (target_state == PSCI_0_2_AFFINITY_LEVEL_OFF)); 58 } while (target_state != PSCI_0_2_AFFINITY_LEVEL_ON); 59 60 GUEST_DONE(); 61 } 62 63 int main(void) 64 { 65 uint64_t target_mpidr, obs_pc, obs_x0; 66 struct kvm_vcpu_init init; 67 struct kvm_vm *vm; 68 struct ucall uc; 69 70 vm = vm_create(VM_MODE_DEFAULT, DEFAULT_GUEST_PHY_PAGES, O_RDWR); 71 kvm_vm_elf_load(vm, program_invocation_name); 72 ucall_init(vm, NULL); 73 74 vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init); 75 init.features[0] |= (1 << KVM_ARM_VCPU_PSCI_0_2); 76 77 aarch64_vcpu_add_default(vm, VCPU_ID_SOURCE, &init, guest_main); 78 79 /* 80 * make sure the target is already off when executing the test. 81 */ 82 init.features[0] |= (1 << KVM_ARM_VCPU_POWER_OFF); 83 aarch64_vcpu_add_default(vm, VCPU_ID_TARGET, &init, guest_main); 84 85 get_reg(vm, VCPU_ID_TARGET, KVM_ARM64_SYS_REG(SYS_MPIDR_EL1), &target_mpidr); 86 vcpu_args_set(vm, VCPU_ID_SOURCE, 1, target_mpidr & MPIDR_HWID_BITMASK); 87 vcpu_run(vm, VCPU_ID_SOURCE); 88 89 switch (get_ucall(vm, VCPU_ID_SOURCE, &uc)) { 90 case UCALL_DONE: 91 break; 92 case UCALL_ABORT: 93 TEST_FAIL("%s at %s:%ld", (const char *)uc.args[0], __FILE__, 94 uc.args[1]); 95 break; 96 default: 97 TEST_FAIL("Unhandled ucall: %lu", uc.cmd); 98 } 99 100 get_reg(vm, VCPU_ID_TARGET, ARM64_CORE_REG(regs.pc), &obs_pc); 101 get_reg(vm, VCPU_ID_TARGET, ARM64_CORE_REG(regs.regs[0]), &obs_x0); 102 103 TEST_ASSERT(obs_pc == CPU_ON_ENTRY_ADDR, 104 "unexpected target cpu pc: %lx (expected: %lx)", 105 obs_pc, CPU_ON_ENTRY_ADDR); 106 TEST_ASSERT(obs_x0 == CPU_ON_CONTEXT_ID, 107 "unexpected target context id: %lx (expected: %lx)", 108 obs_x0, CPU_ON_CONTEXT_ID); 109 110 kvm_vm_free(vm); 111 return 0; 112 } 113