On 13/02/21 01:14, Marc Orr wrote:
From: Ignacio Alvarado ikalvarado@google.com
This test launches 512 VMs in serial and kills them after a random amount of time.
The test was original written to exercise KVM user notifiers in the context of1650b4ebc99d:
- KVM: Disable irq while unregistering user notifier
- https://lore.kernel.org/kvm/CACXrx53vkO=HKfwWwk+fVpvxcNjPrYmtDZ10qWxFvVX_PTG...
Recently, this test piqued my interest because it proved useful to for AMD SNP in exercising the "in-use" pages, described in APM section 15.36.12, "Running SNP-Active Virtual Machines".
To run the test, first compile: $ make "CPPFLAGS=-static -Wl,--whole-archive -lpthread -Wl,--no-whole-archive" \ -C tools/testing/selftests/kvm/
Then, copy the test over to a machine with the kernel and run: $ ./hardware_disable_test
Queued, but these two paragraphs do not belong in an upstream commit message. Thanks!
Paolo
Signed-off-by: Ignacio Alvarado ikalvarado@google.com Signed-off-by: Marc Orr marcorr@google.com
tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/hardware_disable_test.c | 165 ++++++++++++++++++ 3 files changed, 167 insertions(+) create mode 100644 tools/testing/selftests/kvm/hardware_disable_test.c
diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore index ce8f4ad39684..d631e111441a 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -28,6 +28,7 @@ /demand_paging_test /dirty_log_test /dirty_log_perf_test +/hardware_disable_test /kvm_create_max_vcpus /set_memory_region_test /steal_time diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index fe41c6a0fa67..c1c403d878f6 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -62,6 +62,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/tsc_msrs_test TEST_GEN_PROGS_x86_64 += demand_paging_test TEST_GEN_PROGS_x86_64 += dirty_log_test TEST_GEN_PROGS_x86_64 += dirty_log_perf_test +TEST_GEN_PROGS_x86_64 += hardware_disable_test TEST_GEN_PROGS_x86_64 += kvm_create_max_vcpus TEST_GEN_PROGS_x86_64 += set_memory_region_test TEST_GEN_PROGS_x86_64 += steal_time diff --git a/tools/testing/selftests/kvm/hardware_disable_test.c b/tools/testing/selftests/kvm/hardware_disable_test.c new file mode 100644 index 000000000000..2f2eeb8a1d86 --- /dev/null +++ b/tools/testing/selftests/kvm/hardware_disable_test.c @@ -0,0 +1,165 @@ +// 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;
+/* Arguments for the pthreads */ +struct payload {
- struct kvm_vm *vm;
- uint32_t index;
+};
+static void guest_code(void) +{
- for (;;)
; /* Some busy work */- printf("Should not be reached.\n");
+}
+static void *run_vcpu(void *arg) +{
- struct payload *payload = (struct payload *)arg;
- struct kvm_run *state = vcpu_state(payload->vm, payload->index);
- vcpu_run(payload->vm, payload->index);
- TEST_ASSERT(false, "%s: exited with reason %d: %s\n",
__func__, state->exit_reason,exit_reason_str(state->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_vm *vm;
- cpu_set_t cpu_set;
- pthread_t threads[VCPU_NUM];
- pthread_t throw_away;
- struct payload payloads[VCPU_NUM];
- 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(VM_MODE_DEFAULT, DEFAULT_GUEST_PHY_PAGES, O_RDWR);
- kvm_vm_elf_load(vm, program_invocation_name, 0, 0);
- vm_create_irqchip(vm);
- fprintf(stderr, "%s: [%d] start vcpus\n", __func__, run);
- for (i = 0; i < VCPU_NUM; ++i) {
vm_vcpu_add_default(vm, i, guest_code);payloads[i].vm = vm;payloads[i].index = i;check_create_thread(&threads[i], NULL, run_vcpu,(void *)&payloads[i]);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);}- }
- fprintf(stderr, "%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);
+}
+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 */fprintf(stderr, "%s: [%d] waiting semaphore\n", __func__, i);sem_wait(sem);r = (rand() % DELAY_US_MAX) + 1;fprintf(stderr, "%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);fprintf(stderr, "%s: [%d] killing child\n", __func__, i);kill(pid, SIGKILL);- }
- sem_destroy(sem);
- exit(0);
+}