tools/testing/selftests/kvm/steal_time.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * steal/stolen time test
  *
  * Copyright (C) 2020, Red Hat, Inc.
  */
 #define _GNU_SOURCE
 #include <stdio.h>
 #include <time.h>
 #include <sched.h>
 #include <pthread.h>
 #include <linux/kernel.h>
 #include <sys/syscall.h>
 #include <asm/kvm.h>
 #include <asm/kvm_para.h>

 #include "test_util.h"
 #include "kvm_util.h"
 #include "processor.h"

 #define NR_VCPUS		4
 #define ST_GPA_BASE		(1 << 30)
 #define MIN_RUN_DELAY_NS	200000UL

 static void *st_gva[NR_VCPUS];
 static uint64_t guest_stolen_time[NR_VCPUS];

 #if defined(__x86_64__)

 /* steal_time must have 64-byte alignment */
 #define STEAL_TIME_SIZE		((sizeof(struct kvm_steal_time) + 63) & ~63)

 static void check_status(struct kvm_steal_time *st)
 {
 	GUEST_ASSERT(!(READ_ONCE(st->version) & 1));
 	GUEST_ASSERT(READ_ONCE(st->flags) == 0);
 	GUEST_ASSERT(READ_ONCE(st->preempted) == 0);
 }

 static void guest_code(int cpu)
 {
 	struct kvm_steal_time *st = st_gva[cpu];
 	uint32_t version;

 	GUEST_ASSERT(rdmsr(MSR_KVM_STEAL_TIME) == ((uint64_t)st_gva[cpu] | KVM_MSR_ENABLED));

 	memset(st, 0, sizeof(*st));
 	GUEST_SYNC(0);

 	check_status(st);
 	WRITE_ONCE(guest_stolen_time[cpu], st->steal);
 	version = READ_ONCE(st->version);
 	check_status(st);
 	GUEST_SYNC(1);

 	check_status(st);
 	GUEST_ASSERT(version < READ_ONCE(st->version));
 	WRITE_ONCE(guest_stolen_time[cpu], st->steal);
 	check_status(st);
 	GUEST_DONE();
 }

 static void steal_time_init(struct kvm_vm *vm)
 {
 	int i;

 	if (!(kvm_get_supported_cpuid_entry(KVM_CPUID_FEATURES)->eax &
 	      KVM_FEATURE_STEAL_TIME)) {
 		print_skip("steal-time not supported");
 		exit(KSFT_SKIP);
 	}

 	for (i = 0; i < NR_VCPUS; ++i) {
 		int ret;

 		/* ST_GPA_BASE is identity mapped */
 		st_gva[i] = (void *)(ST_GPA_BASE + i * STEAL_TIME_SIZE);
 		sync_global_to_guest(vm, st_gva[i]);

 		ret = _vcpu_set_msr(vm, i, MSR_KVM_STEAL_TIME, (ulong)st_gva[i] | KVM_STEAL_RESERVED_MASK);
 		TEST_ASSERT(ret == 0, "Bad GPA didn't fail");

 		vcpu_set_msr(vm, i, MSR_KVM_STEAL_TIME, (ulong)st_gva[i] | KVM_MSR_ENABLED);
 	}
 }

 static void steal_time_dump(struct kvm_vm *vm, uint32_t vcpuid)
 {
 	struct kvm_steal_time *st = addr_gva2hva(vm, (ulong)st_gva[vcpuid]);
 	int i;

 	pr_info("VCPU%d:\n", vcpuid);
 	pr_info("    steal:     %lld\n", st->steal);
 	pr_info("    version:   %d\n", st->version);
 	pr_info("    flags:     %d\n", st->flags);
 	pr_info("    preempted: %d\n", st->preempted);
 	pr_info("    u8_pad:    ");
 	for (i = 0; i < 3; ++i)
 		pr_info("%d", st->u8_pad[i]);
 	pr_info("\n    pad:       ");
 	for (i = 0; i < 11; ++i)
 		pr_info("%d", st->pad[i]);
 	pr_info("\n");
 }

 #elif defined(__aarch64__)

 /* PV_TIME_ST must have 64-byte alignment */
 #define STEAL_TIME_SIZE		((sizeof(struct st_time) + 63) & ~63)

 #define SMCCC_ARCH_FEATURES	0x80000001
 #define PV_TIME_FEATURES	0xc5000020
 #define PV_TIME_ST		0xc5000021

 struct st_time {
 	uint32_t rev;
 	uint32_t attr;
 	uint64_t st_time;
 };

 static int64_t smccc(uint32_t func, uint32_t arg)
 {
 	unsigned long ret;

 	asm volatile(
 		"mov	x0, %1\n"
 		"mov	x1, %2\n"
 		"hvc	#0\n"
 		"mov	%0, x0\n"
 	: "=r" (ret) : "r" (func), "r" (arg) :
 	  "x0", "x1", "x2", "x3");

 	return ret;
 }

 static void check_status(struct st_time *st)
 {
 	GUEST_ASSERT(READ_ONCE(st->rev) == 0);
 	GUEST_ASSERT(READ_ONCE(st->attr) == 0);
 }

 static void guest_code(int cpu)
 {
 	struct st_time *st;
 	int64_t status;

 	status = smccc(SMCCC_ARCH_FEATURES, PV_TIME_FEATURES);
 	GUEST_ASSERT(status == 0);
 	status = smccc(PV_TIME_FEATURES, PV_TIME_FEATURES);
 	GUEST_ASSERT(status == 0);
 	status = smccc(PV_TIME_FEATURES, PV_TIME_ST);
 	GUEST_ASSERT(status == 0);

 	status = smccc(PV_TIME_ST, 0);
 	GUEST_ASSERT(status != -1);
 	GUEST_ASSERT(status == (ulong)st_gva[cpu]);

 	st = (struct st_time *)status;
 	GUEST_SYNC(0);

 	check_status(st);
 	WRITE_ONCE(guest_stolen_time[cpu], st->st_time);
 	GUEST_SYNC(1);

 	check_status(st);
 	WRITE_ONCE(guest_stolen_time[cpu], st->st_time);
 	GUEST_DONE();
 }

 static void steal_time_init(struct kvm_vm *vm)
 {
 	struct kvm_device_attr dev = {
 		.group = KVM_ARM_VCPU_PVTIME_CTRL,
 		.attr = KVM_ARM_VCPU_PVTIME_IPA,
 	};
 	int i, ret;

 	ret = _vcpu_ioctl(vm, 0, KVM_HAS_DEVICE_ATTR, &dev);
 	if (ret != 0 && errno == ENXIO) {
 		print_skip("steal-time not supported");
 		exit(KSFT_SKIP);
 	}

 	for (i = 0; i < NR_VCPUS; ++i) {
 		uint64_t st_ipa;

 		vcpu_ioctl(vm, i, KVM_HAS_DEVICE_ATTR, &dev);

 		dev.addr = (uint64_t)&st_ipa;

 		/* ST_GPA_BASE is identity mapped */
 		st_gva[i] = (void *)(ST_GPA_BASE + i * STEAL_TIME_SIZE);
 		sync_global_to_guest(vm, st_gva[i]);

 		st_ipa = (ulong)st_gva[i] | 1;
 		ret = _vcpu_ioctl(vm, i, KVM_SET_DEVICE_ATTR, &dev);
 		TEST_ASSERT(ret == -1 && errno == EINVAL, "Bad IPA didn't report EINVAL");

 		st_ipa = (ulong)st_gva[i];
 		vcpu_ioctl(vm, i, KVM_SET_DEVICE_ATTR, &dev);

 		ret = _vcpu_ioctl(vm, i, KVM_SET_DEVICE_ATTR, &dev);
 		TEST_ASSERT(ret == -1 && errno == EEXIST, "Set IPA twice without EEXIST");

 	}
 }

 static void steal_time_dump(struct kvm_vm *vm, uint32_t vcpuid)
 {
 	struct st_time *st = addr_gva2hva(vm, (ulong)st_gva[vcpuid]);

 	pr_info("VCPU%d:\n", vcpuid);
 	pr_info("    rev:     %d\n", st->rev);
 	pr_info("    attr:    %d\n", st->attr);
 	pr_info("    st_time: %ld\n", st->st_time);
 }

 #endif

 static long get_run_delay(void)
 {
 	char path[64];
 	long val[2];
 	FILE *fp;

 	sprintf(path, "/proc/%ld/schedstat", syscall(SYS_gettid));
 	fp = fopen(path, "r");
 	fscanf(fp, "%ld %ld ", &val[0], &val[1]);
 	fclose(fp);

 	return val[1];
 }

 static void *do_steal_time(void *arg)
 {
 	struct timespec ts, stop;

 	clock_gettime(CLOCK_MONOTONIC, &ts);
 	stop = timespec_add_ns(ts, MIN_RUN_DELAY_NS);

 	while (1) {
 		clock_gettime(CLOCK_MONOTONIC, &ts);
 		if (timespec_to_ns(timespec_sub(ts, stop)) >= 0)
 			break;
 	}

 	return NULL;
 }

 static void run_vcpu(struct kvm_vm *vm, uint32_t vcpuid)
 {
 	struct ucall uc;

 	vcpu_args_set(vm, vcpuid, 1, vcpuid);

 	vcpu_ioctl(vm, vcpuid, KVM_RUN, NULL);

 	switch (get_ucall(vm, vcpuid, &uc)) {
 	case UCALL_SYNC:
 	case UCALL_DONE:
 		break;
 	case UCALL_ABORT:
 		TEST_ASSERT(false, "%s at %s:%ld", (const char *)uc.args[0],
 			    __FILE__, uc.args[1]);
 	default:
 		TEST_ASSERT(false, "Unexpected exit: %s",
 			    exit_reason_str(vcpu_state(vm, vcpuid)->exit_reason));
 	}
 }

 int main(int ac, char **av)
 {
 	struct kvm_vm *vm;
 	pthread_attr_t attr;
 	pthread_t thread;
 	cpu_set_t cpuset;
 	unsigned int gpages;
 	long stolen_time;
 	long run_delay;
 	bool verbose;
 	int i;

 	verbose = ac > 1 && (!strncmp(av[1], "-v", 3) || !strncmp(av[1], "--verbose", 10));

 	/* Set CPU affinity so we can force preemption of the VCPU */
 	CPU_ZERO(&cpuset);
 	CPU_SET(0, &cpuset);
 	pthread_attr_init(&attr);
 	pthread_attr_setaffinity_np(&attr, sizeof(cpu_set_t), &cpuset);
 	pthread_setaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpuset);

 	/* Create a one VCPU guest and an identity mapped memslot for the steal time structure */
 	vm = vm_create_default(0, 0, guest_code);
 	gpages = vm_calc_num_guest_pages(VM_MODE_DEFAULT, STEAL_TIME_SIZE * NR_VCPUS);
 	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, ST_GPA_BASE, 1, gpages, 0);
 	virt_map(vm, ST_GPA_BASE, ST_GPA_BASE, gpages);
 	ucall_init(vm, NULL);

 	/* Add the rest of the VCPUs */
 	for (i = 1; i < NR_VCPUS; ++i)
 		vm_vcpu_add_default(vm, i, guest_code);

 	steal_time_init(vm);

 	/* Run test on each VCPU */
 	for (i = 0; i < NR_VCPUS; ++i) {
 		/* First VCPU run initializes steal-time */
 		run_vcpu(vm, i);

 		/* Second VCPU run, expect guest stolen time to be <= run_delay */
 		run_vcpu(vm, i);
 		sync_global_from_guest(vm, guest_stolen_time[i]);
 		stolen_time = guest_stolen_time[i];
 		run_delay = get_run_delay();
 		TEST_ASSERT(stolen_time <= run_delay,
 			    "Expected stolen time <= %ld, got %ld",
 			    run_delay, stolen_time);

 		/* Steal time from the VCPU. The steal time thread has the same CPU affinity as the VCPUs. */
 		run_delay = get_run_delay();
 		pthread_create(&thread, &attr, do_steal_time, NULL);
 		do
 			sched_yield();
 		while (get_run_delay() - run_delay < MIN_RUN_DELAY_NS);
 		pthread_join(thread, NULL);
 		run_delay = get_run_delay() - run_delay;
 		TEST_ASSERT(run_delay >= MIN_RUN_DELAY_NS,
 			    "Expected run_delay >= %ld, got %ld",
 			    MIN_RUN_DELAY_NS, run_delay);

 		/* Run VCPU again to confirm stolen time is consistent with run_delay */
 		run_vcpu(vm, i);
 		sync_global_from_guest(vm, guest_stolen_time[i]);
 		stolen_time = guest_stolen_time[i] - stolen_time;
 		TEST_ASSERT(stolen_time >= run_delay,
 			    "Expected stolen time >= %ld, got %ld",
 			    run_delay, stolen_time);

 		if (verbose) {
 			pr_info("VCPU%d: total-stolen-time=%ld test-stolen-time=%ld", i,
 				guest_stolen_time[i], stolen_time);
 			if (stolen_time == run_delay)
 				pr_info(" (BONUS: guest test-stolen-time even exactly matches test-run_delay)");
 			pr_info("\n");
 			steal_time_dump(vm, i);
 		}
 	}

 	return 0;
 }
	// SPDX-License-Identifier: GPL-2.0
	/*
	* steal/stolen time test
	*
	* Copyright (C) 2020, Red Hat, Inc.
	*/
	#define _GNU_SOURCE
	#include <stdio.h>
	#include <time.h>
	#include <sched.h>
	#include <pthread.h>
	#include <linux/kernel.h>
	#include <sys/syscall.h>
	#include <asm/kvm.h>
	#include <asm/kvm_para.h>

	#include "test_util.h"
	#include "kvm_util.h"
	#include "processor.h"

	#define NR_VCPUS 4
	#define ST_GPA_BASE (1 << 30)
	#define MIN_RUN_DELAY_NS 200000UL

	static void *st_gva[NR_VCPUS];
	static uint64_t guest_stolen_time[NR_VCPUS];

	#if defined(__x86_64__)

	/* steal_time must have 64-byte alignment */
	#define STEAL_TIME_SIZE ((sizeof(struct kvm_steal_time) + 63) & ~63)

	static void check_status(struct kvm_steal_time *st)
	{
	GUEST_ASSERT(!(READ_ONCE(st->version) & 1));
	GUEST_ASSERT(READ_ONCE(st->flags) == 0);
	GUEST_ASSERT(READ_ONCE(st->preempted) == 0);
	}

	static void guest_code(int cpu)
	{
	struct kvm_steal_time *st = st_gva[cpu];
	uint32_t version;

	GUEST_ASSERT(rdmsr(MSR_KVM_STEAL_TIME) == ((uint64_t)st_gva[cpu] \| KVM_MSR_ENABLED));

	memset(st, 0, sizeof(*st));
	GUEST_SYNC(0);

	check_status(st);
	WRITE_ONCE(guest_stolen_time[cpu], st->steal);
	version = READ_ONCE(st->version);
	check_status(st);
	GUEST_SYNC(1);

	check_status(st);
	GUEST_ASSERT(version < READ_ONCE(st->version));
	WRITE_ONCE(guest_stolen_time[cpu], st->steal);
	check_status(st);
	GUEST_DONE();
	}

	static void steal_time_init(struct kvm_vm *vm)
	{
	int i;

	if (!(kvm_get_supported_cpuid_entry(KVM_CPUID_FEATURES)->eax &
	KVM_FEATURE_STEAL_TIME)) {
	print_skip("steal-time not supported");
	exit(KSFT_SKIP);
	}

	for (i = 0; i < NR_VCPUS; ++i) {
	int ret;

	/* ST_GPA_BASE is identity mapped */
	st_gva[i] = (void )(ST_GPA_BASE + i STEAL_TIME_SIZE);
	sync_global_to_guest(vm, st_gva[i]);

	ret = _vcpu_set_msr(vm, i, MSR_KVM_STEAL_TIME, (ulong)st_gva[i] \| KVM_STEAL_RESERVED_MASK);
	TEST_ASSERT(ret == 0, "Bad GPA didn't fail");

	vcpu_set_msr(vm, i, MSR_KVM_STEAL_TIME, (ulong)st_gva[i] \| KVM_MSR_ENABLED);
	}
	}

	static void steal_time_dump(struct kvm_vm *vm, uint32_t vcpuid)
	{
	struct kvm_steal_time *st = addr_gva2hva(vm, (ulong)st_gva[vcpuid]);
	int i;

	pr_info("VCPU%d:\n", vcpuid);
	pr_info(" steal: %lld\n", st->steal);
	pr_info(" version: %d\n", st->version);
	pr_info(" flags: %d\n", st->flags);
	pr_info(" preempted: %d\n", st->preempted);
	pr_info(" u8_pad: ");
	for (i = 0; i < 3; ++i)
	pr_info("%d", st->u8_pad[i]);
	pr_info("\n pad: ");
	for (i = 0; i < 11; ++i)
	pr_info("%d", st->pad[i]);
	pr_info("\n");
	}

	#elif defined(__aarch64__)

	/* PV_TIME_ST must have 64-byte alignment */
	#define STEAL_TIME_SIZE ((sizeof(struct st_time) + 63) & ~63)

	#define SMCCC_ARCH_FEATURES 0x80000001
	#define PV_TIME_FEATURES 0xc5000020
	#define PV_TIME_ST 0xc5000021

	struct st_time {
	uint32_t rev;
	uint32_t attr;
	uint64_t st_time;
	};

	static int64_t smccc(uint32_t func, uint32_t arg)
	{
	unsigned long ret;

	asm volatile(
	"mov x0, %1\n"
	"mov x1, %2\n"
	"hvc #0\n"
	"mov %0, x0\n"
	: "=r" (ret) : "r" (func), "r" (arg) :
	"x0", "x1", "x2", "x3");

	return ret;
	}

	static void check_status(struct st_time *st)
	{
	GUEST_ASSERT(READ_ONCE(st->rev) == 0);
	GUEST_ASSERT(READ_ONCE(st->attr) == 0);
	}

	static void guest_code(int cpu)
	{
	struct st_time *st;
	int64_t status;

	status = smccc(SMCCC_ARCH_FEATURES, PV_TIME_FEATURES);
	GUEST_ASSERT(status == 0);
	status = smccc(PV_TIME_FEATURES, PV_TIME_FEATURES);
	GUEST_ASSERT(status == 0);
	status = smccc(PV_TIME_FEATURES, PV_TIME_ST);
	GUEST_ASSERT(status == 0);

	status = smccc(PV_TIME_ST, 0);
	GUEST_ASSERT(status != -1);
	GUEST_ASSERT(status == (ulong)st_gva[cpu]);

	st = (struct st_time *)status;
	GUEST_SYNC(0);

	check_status(st);
	WRITE_ONCE(guest_stolen_time[cpu], st->st_time);
	GUEST_SYNC(1);

	check_status(st);
	WRITE_ONCE(guest_stolen_time[cpu], st->st_time);
	GUEST_DONE();
	}

	static void steal_time_init(struct kvm_vm *vm)
	{
	struct kvm_device_attr dev = {
	.group = KVM_ARM_VCPU_PVTIME_CTRL,
	.attr = KVM_ARM_VCPU_PVTIME_IPA,
	};
	int i, ret;

	ret = _vcpu_ioctl(vm, 0, KVM_HAS_DEVICE_ATTR, &dev);
	if (ret != 0 && errno == ENXIO) {
	print_skip("steal-time not supported");
	exit(KSFT_SKIP);
	}

	for (i = 0; i < NR_VCPUS; ++i) {
	uint64_t st_ipa;

	vcpu_ioctl(vm, i, KVM_HAS_DEVICE_ATTR, &dev);

	dev.addr = (uint64_t)&st_ipa;

	/* ST_GPA_BASE is identity mapped */
	st_gva[i] = (void )(ST_GPA_BASE + i STEAL_TIME_SIZE);
	sync_global_to_guest(vm, st_gva[i]);

	st_ipa = (ulong)st_gva[i] \| 1;
	ret = _vcpu_ioctl(vm, i, KVM_SET_DEVICE_ATTR, &dev);
	TEST_ASSERT(ret == -1 && errno == EINVAL, "Bad IPA didn't report EINVAL");

	st_ipa = (ulong)st_gva[i];
	vcpu_ioctl(vm, i, KVM_SET_DEVICE_ATTR, &dev);

	ret = _vcpu_ioctl(vm, i, KVM_SET_DEVICE_ATTR, &dev);
	TEST_ASSERT(ret == -1 && errno == EEXIST, "Set IPA twice without EEXIST");

	}
	}

	static void steal_time_dump(struct kvm_vm *vm, uint32_t vcpuid)
	{
	struct st_time *st = addr_gva2hva(vm, (ulong)st_gva[vcpuid]);

	pr_info("VCPU%d:\n", vcpuid);
	pr_info(" rev: %d\n", st->rev);
	pr_info(" attr: %d\n", st->attr);
	pr_info(" st_time: %ld\n", st->st_time);
	}

	#endif

	static long get_run_delay(void)
	{
	char path[64];
	long val[2];
	FILE *fp;

	sprintf(path, "/proc/%ld/schedstat", syscall(SYS_gettid));
	fp = fopen(path, "r");
	fscanf(fp, "%ld %ld ", &val[0], &val[1]);
	fclose(fp);

	return val[1];
	}

	static void do_steal_time(void arg)
	{
	struct timespec ts, stop;

	clock_gettime(CLOCK_MONOTONIC, &ts);
	stop = timespec_add_ns(ts, MIN_RUN_DELAY_NS);

	while (1) {
	clock_gettime(CLOCK_MONOTONIC, &ts);
	if (timespec_to_ns(timespec_sub(ts, stop)) >= 0)
	break;
	}

	return NULL;
	}

	static void run_vcpu(struct kvm_vm *vm, uint32_t vcpuid)
	{
	struct ucall uc;

	vcpu_args_set(vm, vcpuid, 1, vcpuid);

	vcpu_ioctl(vm, vcpuid, KVM_RUN, NULL);

	switch (get_ucall(vm, vcpuid, &uc)) {
	case UCALL_SYNC:
	case UCALL_DONE:
	break;
	case UCALL_ABORT:
	TEST_ASSERT(false, "%s at %s:%ld", (const char *)uc.args[0],
	__FILE__, uc.args[1]);
	default:
	TEST_ASSERT(false, "Unexpected exit: %s",
	exit_reason_str(vcpu_state(vm, vcpuid)->exit_reason));
	}
	}

	int main(int ac, char **av)
	{
	struct kvm_vm *vm;
	pthread_attr_t attr;
	pthread_t thread;
	cpu_set_t cpuset;
	unsigned int gpages;
	long stolen_time;
	long run_delay;
	bool verbose;
	int i;

	verbose = ac > 1 && (!strncmp(av[1], "-v", 3) \|\| !strncmp(av[1], "--verbose", 10));

	/* Set CPU affinity so we can force preemption of the VCPU */
	CPU_ZERO(&cpuset);
	CPU_SET(0, &cpuset);
	pthread_attr_init(&attr);
	pthread_attr_setaffinity_np(&attr, sizeof(cpu_set_t), &cpuset);
	pthread_setaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpuset);

	/* Create a one VCPU guest and an identity mapped memslot for the steal time structure */
	vm = vm_create_default(0, 0, guest_code);
	gpages = vm_calc_num_guest_pages(VM_MODE_DEFAULT, STEAL_TIME_SIZE * NR_VCPUS);
	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, ST_GPA_BASE, 1, gpages, 0);
	virt_map(vm, ST_GPA_BASE, ST_GPA_BASE, gpages);
	ucall_init(vm, NULL);

	/* Add the rest of the VCPUs */
	for (i = 1; i < NR_VCPUS; ++i)
	vm_vcpu_add_default(vm, i, guest_code);

	steal_time_init(vm);

	/* Run test on each VCPU */
	for (i = 0; i < NR_VCPUS; ++i) {
	/* First VCPU run initializes steal-time */
	run_vcpu(vm, i);

	/* Second VCPU run, expect guest stolen time to be <= run_delay */
	run_vcpu(vm, i);
	sync_global_from_guest(vm, guest_stolen_time[i]);
	stolen_time = guest_stolen_time[i];
	run_delay = get_run_delay();
	TEST_ASSERT(stolen_time <= run_delay,
	"Expected stolen time <= %ld, got %ld",
	run_delay, stolen_time);

	/* Steal time from the VCPU. The steal time thread has the same CPU affinity as the VCPUs. */
	run_delay = get_run_delay();
	pthread_create(&thread, &attr, do_steal_time, NULL);
	do
	sched_yield();
	while (get_run_delay() - run_delay < MIN_RUN_DELAY_NS);
	pthread_join(thread, NULL);
	run_delay = get_run_delay() - run_delay;
	TEST_ASSERT(run_delay >= MIN_RUN_DELAY_NS,
	"Expected run_delay >= %ld, got %ld",
	MIN_RUN_DELAY_NS, run_delay);

	/* Run VCPU again to confirm stolen time is consistent with run_delay */
	run_vcpu(vm, i);
	sync_global_from_guest(vm, guest_stolen_time[i]);
	stolen_time = guest_stolen_time[i] - stolen_time;
	TEST_ASSERT(stolen_time >= run_delay,
	"Expected stolen time >= %ld, got %ld",
	run_delay, stolen_time);

	if (verbose) {
	pr_info("VCPU%d: total-stolen-time=%ld test-stolen-time=%ld", i,
	guest_stolen_time[i], stolen_time);
	if (stolen_time == run_delay)
	pr_info(" (BONUS: guest test-stolen-time even exactly matches test-run_delay)");
	pr_info("\n");
	steal_time_dump(vm, i);
	}
	}

	return 0;
	}