1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * psci_test - Tests relating to KVM's PSCI implementation.
4 *
5 * Copyright (c) 2021 Google LLC.
6 *
7 * This test includes:
8 * - A regression test for a race between KVM servicing the PSCI CPU_ON call
9 * and userspace reading the targeted vCPU's registers.
10 * - A test for KVM's handling of PSCI SYSTEM_SUSPEND and the associated
11 * KVM_SYSTEM_EVENT_SUSPEND UAPI.
12 */
13
14 #define _GNU_SOURCE
15
16 #include <linux/psci.h>
17
18 #include "kvm_util.h"
19 #include "processor.h"
20 #include "test_util.h"
21
22 #define CPU_ON_ENTRY_ADDR 0xfeedf00dul
23 #define CPU_ON_CONTEXT_ID 0xdeadc0deul
24
psci_cpu_on(uint64_t target_cpu,uint64_t entry_addr,uint64_t context_id)25 static uint64_t psci_cpu_on(uint64_t target_cpu, uint64_t entry_addr,
26 uint64_t context_id)
27 {
28 struct arm_smccc_res res;
29
30 smccc_hvc(PSCI_0_2_FN64_CPU_ON, target_cpu, entry_addr, context_id,
31 0, 0, 0, 0, &res);
32
33 return res.a0;
34 }
35
psci_affinity_info(uint64_t target_affinity,uint64_t lowest_affinity_level)36 static uint64_t psci_affinity_info(uint64_t target_affinity,
37 uint64_t lowest_affinity_level)
38 {
39 struct arm_smccc_res res;
40
41 smccc_hvc(PSCI_0_2_FN64_AFFINITY_INFO, target_affinity, lowest_affinity_level,
42 0, 0, 0, 0, 0, &res);
43
44 return res.a0;
45 }
46
psci_system_suspend(uint64_t entry_addr,uint64_t context_id)47 static uint64_t psci_system_suspend(uint64_t entry_addr, uint64_t context_id)
48 {
49 struct arm_smccc_res res;
50
51 smccc_hvc(PSCI_1_0_FN64_SYSTEM_SUSPEND, entry_addr, context_id,
52 0, 0, 0, 0, 0, &res);
53
54 return res.a0;
55 }
56
psci_features(uint32_t func_id)57 static uint64_t psci_features(uint32_t func_id)
58 {
59 struct arm_smccc_res res;
60
61 smccc_hvc(PSCI_1_0_FN_PSCI_FEATURES, func_id, 0, 0, 0, 0, 0, 0, &res);
62
63 return res.a0;
64 }
65
vcpu_power_off(struct kvm_vcpu * vcpu)66 static void vcpu_power_off(struct kvm_vcpu *vcpu)
67 {
68 struct kvm_mp_state mp_state = {
69 .mp_state = KVM_MP_STATE_STOPPED,
70 };
71
72 vcpu_mp_state_set(vcpu, &mp_state);
73 }
74
setup_vm(void * guest_code,struct kvm_vcpu ** source,struct kvm_vcpu ** target)75 static struct kvm_vm *setup_vm(void *guest_code, struct kvm_vcpu **source,
76 struct kvm_vcpu **target)
77 {
78 struct kvm_vcpu_init init;
79 struct kvm_vm *vm;
80
81 vm = vm_create(2);
82 ucall_init(vm, NULL);
83
84 vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init);
85 init.features[0] |= (1 << KVM_ARM_VCPU_PSCI_0_2);
86
87 *source = aarch64_vcpu_add(vm, 0, &init, guest_code);
88 *target = aarch64_vcpu_add(vm, 1, &init, guest_code);
89
90 return vm;
91 }
92
enter_guest(struct kvm_vcpu * vcpu)93 static void enter_guest(struct kvm_vcpu *vcpu)
94 {
95 struct ucall uc;
96
97 vcpu_run(vcpu);
98 if (get_ucall(vcpu, &uc) == UCALL_ABORT)
99 REPORT_GUEST_ASSERT(uc);
100 }
101
assert_vcpu_reset(struct kvm_vcpu * vcpu)102 static void assert_vcpu_reset(struct kvm_vcpu *vcpu)
103 {
104 uint64_t obs_pc, obs_x0;
105
106 vcpu_get_reg(vcpu, ARM64_CORE_REG(regs.pc), &obs_pc);
107 vcpu_get_reg(vcpu, ARM64_CORE_REG(regs.regs[0]), &obs_x0);
108
109 TEST_ASSERT(obs_pc == CPU_ON_ENTRY_ADDR,
110 "unexpected target cpu pc: %lx (expected: %lx)",
111 obs_pc, CPU_ON_ENTRY_ADDR);
112 TEST_ASSERT(obs_x0 == CPU_ON_CONTEXT_ID,
113 "unexpected target context id: %lx (expected: %lx)",
114 obs_x0, CPU_ON_CONTEXT_ID);
115 }
116
guest_test_cpu_on(uint64_t target_cpu)117 static void guest_test_cpu_on(uint64_t target_cpu)
118 {
119 uint64_t target_state;
120
121 GUEST_ASSERT(!psci_cpu_on(target_cpu, CPU_ON_ENTRY_ADDR, CPU_ON_CONTEXT_ID));
122
123 do {
124 target_state = psci_affinity_info(target_cpu, 0);
125
126 GUEST_ASSERT((target_state == PSCI_0_2_AFFINITY_LEVEL_ON) ||
127 (target_state == PSCI_0_2_AFFINITY_LEVEL_OFF));
128 } while (target_state != PSCI_0_2_AFFINITY_LEVEL_ON);
129
130 GUEST_DONE();
131 }
132
host_test_cpu_on(void)133 static void host_test_cpu_on(void)
134 {
135 struct kvm_vcpu *source, *target;
136 uint64_t target_mpidr;
137 struct kvm_vm *vm;
138 struct ucall uc;
139
140 vm = setup_vm(guest_test_cpu_on, &source, &target);
141
142 /*
143 * make sure the target is already off when executing the test.
144 */
145 vcpu_power_off(target);
146
147 vcpu_get_reg(target, KVM_ARM64_SYS_REG(SYS_MPIDR_EL1), &target_mpidr);
148 vcpu_args_set(source, 1, target_mpidr & MPIDR_HWID_BITMASK);
149 enter_guest(source);
150
151 if (get_ucall(source, &uc) != UCALL_DONE)
152 TEST_FAIL("Unhandled ucall: %lu", uc.cmd);
153
154 assert_vcpu_reset(target);
155 kvm_vm_free(vm);
156 }
157
guest_test_system_suspend(void)158 static void guest_test_system_suspend(void)
159 {
160 uint64_t ret;
161
162 /* assert that SYSTEM_SUSPEND is discoverable */
163 GUEST_ASSERT(!psci_features(PSCI_1_0_FN_SYSTEM_SUSPEND));
164 GUEST_ASSERT(!psci_features(PSCI_1_0_FN64_SYSTEM_SUSPEND));
165
166 ret = psci_system_suspend(CPU_ON_ENTRY_ADDR, CPU_ON_CONTEXT_ID);
167 GUEST_SYNC(ret);
168 }
169
host_test_system_suspend(void)170 static void host_test_system_suspend(void)
171 {
172 struct kvm_vcpu *source, *target;
173 struct kvm_run *run;
174 struct kvm_vm *vm;
175
176 vm = setup_vm(guest_test_system_suspend, &source, &target);
177 vm_enable_cap(vm, KVM_CAP_ARM_SYSTEM_SUSPEND, 0);
178
179 vcpu_power_off(target);
180 run = source->run;
181
182 enter_guest(source);
183
184 TEST_ASSERT(run->exit_reason == KVM_EXIT_SYSTEM_EVENT,
185 "Unhandled exit reason: %u (%s)",
186 run->exit_reason, exit_reason_str(run->exit_reason));
187 TEST_ASSERT(run->system_event.type == KVM_SYSTEM_EVENT_SUSPEND,
188 "Unhandled system event: %u (expected: %u)",
189 run->system_event.type, KVM_SYSTEM_EVENT_SUSPEND);
190
191 kvm_vm_free(vm);
192 }
193
main(void)194 int main(void)
195 {
196 TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_SYSTEM_SUSPEND));
197
198 host_test_cpu_on();
199 host_test_system_suspend();
200 return 0;
201 }
202