Added a selftest set_memory_region_io to test memslots for MMIO BARs. The MMIO BARs' backends are compound/non-compound huge pages serving as device resources allocated by a mock device driver.
This selftest will assert and report "errno=14 - Bad address" in vcpu_run() if any failure is met to add such MMIO BAR memslots. After MMIO memslots removal, page reference counts of the device resources are also checked. As this selftest will interacts with a mock device "/dev/kvm_mock_device", it depends on test driver test_kvm_mock_device.ko in the kernel. CONFIG_TEST_KVM_MOCK_DEVICE=m must be enabled in the kernel. Currently, this selftest is only compiled for __x86_64__. Signed-off-by: Yan Zhao <[email protected]> --- tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/set_memory_region_io.c | 188 ++++++++++++++++++ 2 files changed, 189 insertions(+) create mode 100644 tools/testing/selftests/kvm/set_memory_region_io.c diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 4412b42d95de..9d39514b6403 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -144,6 +144,7 @@ TEST_GEN_PROGS_x86_64 += memslot_modification_stress_test TEST_GEN_PROGS_x86_64 += memslot_perf_test TEST_GEN_PROGS_x86_64 += rseq_test TEST_GEN_PROGS_x86_64 += set_memory_region_test +TEST_GEN_PROGS_x86_64 += set_memory_region_io TEST_GEN_PROGS_x86_64 += steal_time TEST_GEN_PROGS_x86_64 += kvm_binary_stats_test TEST_GEN_PROGS_x86_64 += system_counter_offset_test diff --git a/tools/testing/selftests/kvm/set_memory_region_io.c b/tools/testing/selftests/kvm/set_memory_region_io.c new file mode 100644 index 000000000000..e221103091f4 --- /dev/null +++ b/tools/testing/selftests/kvm/set_memory_region_io.c @@ -0,0 +1,188 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _GNU_SOURCE /* for program_invocation_short_name */ +#include <fcntl.h> +#include <pthread.h> +#include <sched.h> +#include <semaphore.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ioctl.h> +#include <sys/mman.h> + +#include <linux/compiler.h> + +#include <test_util.h> +#include <kvm_util.h> +#include <processor.h> + +#include <../../../../lib/test_kvm_mock_device_uapi.h> + +/* + * Somewhat arbitrary location and slot, intended to not overlap anything. + */ +#define MEM_REGION_GPA_BASE 0xc0000000 +#define RANDOM_OFFSET 0x1000 +#define MEM_REGION_GPA_RANDOM (MEM_REGION_GPA_BASE + RANDOM_OFFSET) +#define MEM_REGION_SLOT_ID 10 + +static const bool non_compound_supported; + +static const uint64_t BASE_VAL = 0x1111; +static const uint64_t RANDOM_VAL = 0x2222; + +static unsigned long bar_size; + +static sem_t vcpu_ready; + +static void guest_code_read_bar(void) +{ + uint64_t val; + + GUEST_SYNC(0); + + val = READ_ONCE(*((uint64_t *)MEM_REGION_GPA_RANDOM)); + GUEST_ASSERT_EQ(val, RANDOM_VAL); + + val = READ_ONCE(*((uint64_t *)MEM_REGION_GPA_BASE)); + GUEST_ASSERT_EQ(val, BASE_VAL); + + GUEST_DONE(); +} + +static void *vcpu_worker(void *data) +{ + struct kvm_vcpu *vcpu = data; + struct kvm_run *run = vcpu->run; + struct ucall uc; + uint64_t cmd; + + /* + * Loop until the guest is done. Re-enter the guest on all MMIO exits, + * which will occur if the guest attempts to access a memslot after it + * has been deleted or while it is being moved . + */ + while (1) { + vcpu_run(vcpu); + + if (run->exit_reason == KVM_EXIT_IO) { + cmd = get_ucall(vcpu, &uc); + if (cmd != UCALL_SYNC) + break; + + sem_post(&vcpu_ready); + continue; + } + + if (run->exit_reason != KVM_EXIT_MMIO) + break; + + TEST_ASSERT(!run->mmio.is_write, "Unexpected exit mmio write"); + TEST_ASSERT(run->mmio.len == 8, + "Unexpected exit mmio size = %u", run->mmio.len); + + TEST_ASSERT(run->mmio.phys_addr < MEM_REGION_GPA_BASE || + run->mmio.phys_addr >= MEM_REGION_GPA_BASE + bar_size, + "Unexpected exit mmio address = 0x%llx", + run->mmio.phys_addr); + } + + if (run->exit_reason == KVM_EXIT_IO && cmd == UCALL_ABORT) + REPORT_GUEST_ASSERT(uc); + + return NULL; +} + +static void wait_for_vcpu(void) +{ + struct timespec ts; + + TEST_ASSERT(!clock_gettime(CLOCK_REALTIME, &ts), + "clock_gettime() failed: %d\n", errno); + + ts.tv_sec += 2; + TEST_ASSERT(!sem_timedwait(&vcpu_ready, &ts), + "sem_timedwait() failed: %d\n", errno); + + /* Wait for the vCPU thread to reenter the guest. */ + usleep(100000); +} + +static void test_kvm_mock_device_bar(bool compound) +{ + struct kvm_vm *vm; + void *mem; + struct kvm_vcpu *vcpu; + pthread_t vcpu_thread; + int fd, ret; + u32 param_compound = compound; + u32 inequal = 0; + + fd = open("/dev/kvm_mock_device", O_RDWR); + if (fd < 0) { + pr_info("Please ensure \"CONFIG_TEST_KVM_MOCK_DEVICE=m\" is enabled in the kernel"); + pr_info(", and execute\n\"modprobe test_kvm_mock_device\n"); + } + TEST_ASSERT(fd >= 0, "Failed to open kvm mock device."); + + ret = ioctl(fd, KVM_MOCK_DEVICE_GET_BAR_SIZE, &bar_size); + TEST_ASSERT(ret == 0, "Failed to get bar size of kvm mock device"); + + ret = ioctl(fd, KVM_MOCK_DEVICE_PREPARE_RESOURCE, ¶m_compound); + TEST_ASSERT(ret == 0, "Failed to prepare resource of kvm mock device"); + + mem = mmap(NULL, (size_t)bar_size, PROT_READ | PROT_WRITE, MAP_SHARED, + fd, 0); + TEST_ASSERT(mem != MAP_FAILED, "Failed to mmap() kvm mock device bar"); + + *(u64 *)mem = BASE_VAL; + *(u64 *)(mem + RANDOM_OFFSET) = RANDOM_VAL; + + vm = vm_create_with_one_vcpu(&vcpu, guest_code_read_bar); + + vm_set_user_memory_region(vm, MEM_REGION_SLOT_ID, 0, MEM_REGION_GPA_BASE, + bar_size, mem); + + virt_map(vm, MEM_REGION_GPA_BASE, MEM_REGION_GPA_BASE, + (RANDOM_OFFSET / getpagesize()) + 1); + + pthread_create(&vcpu_thread, NULL, vcpu_worker, vcpu); + + /* Ensure the guest thread is spun up. */ + wait_for_vcpu(); + + pthread_join(vcpu_thread, NULL); + + vm_set_user_memory_region(vm, MEM_REGION_SLOT_ID, 0, 0, 0, 0); + kvm_vm_free(vm); + + ret = ioctl(fd, KVM_MOCK_DEVICE_CHECK_BACKEND_REF, &inequal); + TEST_ASSERT(ret == 0 && inequal == 0, "Incorrect resource ref of KVM device"); + + munmap(mem, bar_size); + close(fd); +} + +static void test_non_compound_backend(void) +{ + pr_info("Testing non-compound huge page backend for mem slot\n"); + test_kvm_mock_device_bar(false); +} + +static void test_compound_backend(void) +{ + pr_info("Testing compound huge page backend for mem slot\n"); + test_kvm_mock_device_bar(true); +} + +int main(int argc, char *argv[]) +{ +#ifdef __x86_64__ + test_compound_backend(); + if (non_compound_supported) + test_non_compound_backend(); +#endif + + return 0; +} -- 2.17.1
