linux/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c

127 lines
2.6 KiB
C

/*
* mmio_warning_test
*
* Copyright (C) 2019, Google LLC.
*
* This work is licensed under the terms of the GNU GPL, version 2.
*
* Test that we don't get a kernel warning when we call KVM_RUN after a
* triple fault occurs. To get the triple fault to occur we call KVM_RUN
* on a VCPU that hasn't been properly setup.
*
*/
#define _GNU_SOURCE
#include <fcntl.h>
#include <kvm_util.h>
#include <linux/kvm.h>
#include <processor.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <test_util.h>
#include <unistd.h>
#define NTHREAD 4
#define NPROCESS 5
struct thread_context {
int kvmcpu;
struct kvm_run *run;
};
void *thr(void *arg)
{
struct thread_context *tc = (struct thread_context *)arg;
int res;
int kvmcpu = tc->kvmcpu;
struct kvm_run *run = tc->run;
res = ioctl(kvmcpu, KVM_RUN, 0);
pr_info("ret1=%d exit_reason=%d suberror=%d\n",
res, run->exit_reason, run->internal.suberror);
return 0;
}
void test(void)
{
int i, kvm, kvmvm, kvmcpu;
pthread_t th[NTHREAD];
struct kvm_run *run;
struct thread_context tc;
kvm = open("/dev/kvm", O_RDWR);
TEST_ASSERT(kvm != -1, "failed to open /dev/kvm");
kvmvm = ioctl(kvm, KVM_CREATE_VM, 0);
TEST_ASSERT(kvmvm != -1, "KVM_CREATE_VM failed");
kvmcpu = ioctl(kvmvm, KVM_CREATE_VCPU, 0);
TEST_ASSERT(kvmcpu != -1, "KVM_CREATE_VCPU failed");
run = (struct kvm_run *)mmap(0, 4096, PROT_READ|PROT_WRITE, MAP_SHARED,
kvmcpu, 0);
tc.kvmcpu = kvmcpu;
tc.run = run;
srand(getpid());
for (i = 0; i < NTHREAD; i++) {
pthread_create(&th[i], NULL, thr, (void *)(uintptr_t)&tc);
usleep(rand() % 10000);
}
for (i = 0; i < NTHREAD; i++)
pthread_join(th[i], NULL);
}
int get_warnings_count(void)
{
int warnings;
FILE *f;
f = popen("dmesg | grep \"WARNING:\" | wc -l", "r");
fscanf(f, "%d", &warnings);
fclose(f);
return warnings;
}
int main(void)
{
int warnings_before, warnings_after;
if (!is_intel_cpu()) {
print_skip("Must be run on an Intel CPU");
exit(KSFT_SKIP);
}
if (vm_is_unrestricted_guest(NULL)) {
print_skip("Unrestricted guest must be disabled");
exit(KSFT_SKIP);
}
warnings_before = get_warnings_count();
for (int i = 0; i < NPROCESS; ++i) {
int status;
int pid = fork();
if (pid < 0)
exit(1);
if (pid == 0) {
test();
exit(0);
}
while (waitpid(pid, &status, __WALL) != pid)
;
}
warnings_after = get_warnings_count();
TEST_ASSERT(warnings_before == warnings_after,
"Warnings found in kernel. Run 'dmesg' to inspect them.");
return 0;
}