| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * psci_cpu_on_test - Test that the observable state of a vCPU targeted by the |
| * CPU_ON PSCI call matches what the caller requested. |
| * |
| * Copyright (c) 2021 Google LLC. |
| * |
| * This is a regression test for a race between KVM servicing the PSCI call and |
| * userspace reading the vCPUs registers. |
| */ |
| |
| #define _GNU_SOURCE |
| |
| #include <linux/psci.h> |
| |
| #include "kvm_util.h" |
| #include "processor.h" |
| #include "test_util.h" |
| |
| #define VCPU_ID_SOURCE 0 |
| #define VCPU_ID_TARGET 1 |
| |
| #define CPU_ON_ENTRY_ADDR 0xfeedf00dul |
| #define CPU_ON_CONTEXT_ID 0xdeadc0deul |
| |
| static uint64_t psci_cpu_on(uint64_t target_cpu, uint64_t entry_addr, |
| uint64_t context_id) |
| { |
| register uint64_t x0 asm("x0") = PSCI_0_2_FN64_CPU_ON; |
| register uint64_t x1 asm("x1") = target_cpu; |
| register uint64_t x2 asm("x2") = entry_addr; |
| register uint64_t x3 asm("x3") = context_id; |
| |
| asm("hvc #0" |
| : "=r"(x0) |
| : "r"(x0), "r"(x1), "r"(x2), "r"(x3) |
| : "memory"); |
| |
| return x0; |
| } |
| |
| static uint64_t psci_affinity_info(uint64_t target_affinity, |
| uint64_t lowest_affinity_level) |
| { |
| register uint64_t x0 asm("x0") = PSCI_0_2_FN64_AFFINITY_INFO; |
| register uint64_t x1 asm("x1") = target_affinity; |
| register uint64_t x2 asm("x2") = lowest_affinity_level; |
| |
| asm("hvc #0" |
| : "=r"(x0) |
| : "r"(x0), "r"(x1), "r"(x2) |
| : "memory"); |
| |
| return x0; |
| } |
| |
| static void guest_main(uint64_t target_cpu) |
| { |
| GUEST_ASSERT(!psci_cpu_on(target_cpu, CPU_ON_ENTRY_ADDR, CPU_ON_CONTEXT_ID)); |
| uint64_t target_state; |
| |
| do { |
| target_state = psci_affinity_info(target_cpu, 0); |
| |
| GUEST_ASSERT((target_state == PSCI_0_2_AFFINITY_LEVEL_ON) || |
| (target_state == PSCI_0_2_AFFINITY_LEVEL_OFF)); |
| } while (target_state != PSCI_0_2_AFFINITY_LEVEL_ON); |
| |
| GUEST_DONE(); |
| } |
| |
| int main(void) |
| { |
| uint64_t target_mpidr, obs_pc, obs_x0; |
| struct kvm_vcpu_init init; |
| struct kvm_vm *vm; |
| struct ucall uc; |
| |
| vm = vm_create(VM_MODE_DEFAULT, DEFAULT_GUEST_PHY_PAGES, O_RDWR); |
| kvm_vm_elf_load(vm, program_invocation_name); |
| ucall_init(vm, NULL); |
| |
| vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init); |
| init.features[0] |= (1 << KVM_ARM_VCPU_PSCI_0_2); |
| |
| aarch64_vcpu_add_default(vm, VCPU_ID_SOURCE, &init, guest_main); |
| |
| /* |
| * make sure the target is already off when executing the test. |
| */ |
| init.features[0] |= (1 << KVM_ARM_VCPU_POWER_OFF); |
| aarch64_vcpu_add_default(vm, VCPU_ID_TARGET, &init, guest_main); |
| |
| get_reg(vm, VCPU_ID_TARGET, ARM64_SYS_REG(MPIDR_EL1), &target_mpidr); |
| vcpu_args_set(vm, VCPU_ID_SOURCE, 1, target_mpidr & MPIDR_HWID_BITMASK); |
| vcpu_run(vm, VCPU_ID_SOURCE); |
| |
| switch (get_ucall(vm, VCPU_ID_SOURCE, &uc)) { |
| case UCALL_DONE: |
| break; |
| case UCALL_ABORT: |
| TEST_FAIL("%s at %s:%ld", (const char *)uc.args[0], __FILE__, |
| uc.args[1]); |
| break; |
| default: |
| TEST_FAIL("Unhandled ucall: %lu", uc.cmd); |
| } |
| |
| get_reg(vm, VCPU_ID_TARGET, ARM64_CORE_REG(regs.pc), &obs_pc); |
| get_reg(vm, VCPU_ID_TARGET, ARM64_CORE_REG(regs.regs[0]), &obs_x0); |
| |
| TEST_ASSERT(obs_pc == CPU_ON_ENTRY_ADDR, |
| "unexpected target cpu pc: %lx (expected: %lx)", |
| obs_pc, CPU_ON_ENTRY_ADDR); |
| TEST_ASSERT(obs_x0 == CPU_ON_CONTEXT_ID, |
| "unexpected target context id: %lx (expected: %lx)", |
| obs_x0, CPU_ON_CONTEXT_ID); |
| |
| kvm_vm_free(vm); |
| return 0; |
| } |