blob: f5d59b9934f184163e3e1e48578508d2a5255eae [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* This test is intended to reproduce a crash that happens when
* kvm_arch_hardware_disable is called and it attempts to unregister the user
* return notifiers.
*/
#define _GNU_SOURCE
#include <fcntl.h>
#include <pthread.h>
#include <semaphore.h>
#include <stdint.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/wait.h>
#include <test_util.h>
#include "kvm_util.h"
#define VCPU_NUM 4
#define SLEEPING_THREAD_NUM (1 << 4)
#define FORK_NUM (1ULL << 9)
#define DELAY_US_MAX 2000
#define GUEST_CODE_PIO_PORT 4
sem_t *sem;
static void guest_code(void)
{
for (;;)
; /* Some busy work */
printf("Should not be reached.\n");
}
static void *run_vcpu(void *arg)
{
struct kvm_vcpu *vcpu = arg;
struct kvm_run *run = vcpu->run;
vcpu_run(vcpu);
TEST_ASSERT(false, "%s: exited with reason %d: %s\n",
__func__, run->exit_reason,
exit_reason_str(run->exit_reason));
pthread_exit(NULL);
}
static void *sleeping_thread(void *arg)
{
int fd;
while (true) {
fd = open("/dev/null", O_RDWR);
close(fd);
}
TEST_ASSERT(false, "%s: exited\n", __func__);
pthread_exit(NULL);
}
static inline void check_create_thread(pthread_t *thread, pthread_attr_t *attr,
void *(*f)(void *), void *arg)
{
int r;
r = pthread_create(thread, attr, f, arg);
TEST_ASSERT(r == 0, "%s: failed to create thread", __func__);
}
static inline void check_set_affinity(pthread_t thread, cpu_set_t *cpu_set)
{
int r;
r = pthread_setaffinity_np(thread, sizeof(cpu_set_t), cpu_set);
TEST_ASSERT(r == 0, "%s: failed set affinity", __func__);
}
static inline void check_join(pthread_t thread, void **retval)
{
int r;
r = pthread_join(thread, retval);
TEST_ASSERT(r == 0, "%s: failed to join thread", __func__);
}
static void run_test(uint32_t run)
{
struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
cpu_set_t cpu_set;
pthread_t threads[VCPU_NUM];
pthread_t throw_away;
void *b;
uint32_t i, j;
CPU_ZERO(&cpu_set);
for (i = 0; i < VCPU_NUM; i++)
CPU_SET(i, &cpu_set);
vm = vm_create(VCPU_NUM);
pr_debug("%s: [%d] start vcpus\n", __func__, run);
for (i = 0; i < VCPU_NUM; ++i) {
vcpu = vm_vcpu_add(vm, i, guest_code);
check_create_thread(&threads[i], NULL, run_vcpu, vcpu);
check_set_affinity(threads[i], &cpu_set);
for (j = 0; j < SLEEPING_THREAD_NUM; ++j) {
check_create_thread(&throw_away, NULL, sleeping_thread,
(void *)NULL);
check_set_affinity(throw_away, &cpu_set);
}
}
pr_debug("%s: [%d] all threads launched\n", __func__, run);
sem_post(sem);
for (i = 0; i < VCPU_NUM; ++i)
check_join(threads[i], &b);
/* Should not be reached */
TEST_ASSERT(false, "%s: [%d] child escaped the ninja\n", __func__, run);
}
void wait_for_child_setup(pid_t pid)
{
/*
* Wait for the child to post to the semaphore, but wake up periodically
* to check if the child exited prematurely.
*/
for (;;) {
const struct timespec wait_period = { .tv_sec = 1 };
int status;
if (!sem_timedwait(sem, &wait_period))
return;
/* Child is still running, keep waiting. */
if (pid != waitpid(pid, &status, WNOHANG))
continue;
/*
* Child is no longer running, which is not expected.
*
* If it exited with a non-zero status, we explicitly forward
* the child's status in case it exited with KSFT_SKIP.
*/
if (WIFEXITED(status))
exit(WEXITSTATUS(status));
else
TEST_ASSERT(false, "Child exited unexpectedly");
}
}
int main(int argc, char **argv)
{
uint32_t i;
int s, r;
pid_t pid;
sem = sem_open("vm_sem", O_CREAT | O_EXCL, 0644, 0);
sem_unlink("vm_sem");
for (i = 0; i < FORK_NUM; ++i) {
pid = fork();
TEST_ASSERT(pid >= 0, "%s: unable to fork", __func__);
if (pid == 0)
run_test(i); /* This function always exits */
pr_debug("%s: [%d] waiting semaphore\n", __func__, i);
wait_for_child_setup(pid);
r = (rand() % DELAY_US_MAX) + 1;
pr_debug("%s: [%d] waiting %dus\n", __func__, i, r);
usleep(r);
r = waitpid(pid, &s, WNOHANG);
TEST_ASSERT(r != pid,
"%s: [%d] child exited unexpectedly status: [%d]",
__func__, i, s);
pr_debug("%s: [%d] killing child\n", __func__, i);
kill(pid, SIGKILL);
}
sem_destroy(sem);
exit(0);
}