This patch introduces the mem_slot_test test which checks an VM can have added memory slots up to the limit defined in KVM_CAP_NR_MEMSLOTS. Then attempt to add one more slot to verify it fails as expected.
Signed-off-by: Wainer dos Santos Moschetta wainersm@redhat.com --- tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 3 + tools/testing/selftests/kvm/mem_slot_test.c | 76 +++++++++++++++++++++ 3 files changed, 80 insertions(+) create mode 100644 tools/testing/selftests/kvm/mem_slot_test.c
diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore index 16877c3daabf..127d27188427 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -21,4 +21,5 @@ /demand_paging_test /dirty_log_test /kvm_create_max_vcpus +/mem_slot_test /steal_time diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 712a2ddd2a27..338b6cdce1a0 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -32,12 +32,14 @@ TEST_GEN_PROGS_x86_64 += clear_dirty_log_test TEST_GEN_PROGS_x86_64 += demand_paging_test TEST_GEN_PROGS_x86_64 += dirty_log_test TEST_GEN_PROGS_x86_64 += kvm_create_max_vcpus +TEST_GEN_PROGS_x86_64 += mem_slot_test TEST_GEN_PROGS_x86_64 += steal_time
TEST_GEN_PROGS_aarch64 += clear_dirty_log_test TEST_GEN_PROGS_aarch64 += demand_paging_test TEST_GEN_PROGS_aarch64 += dirty_log_test TEST_GEN_PROGS_aarch64 += kvm_create_max_vcpus +TEST_GEN_PROGS_aarch64 += mem_slot_test TEST_GEN_PROGS_aarch64 += steal_time
TEST_GEN_PROGS_s390x = s390x/memop @@ -46,6 +48,7 @@ TEST_GEN_PROGS_s390x += s390x/sync_regs_test TEST_GEN_PROGS_s390x += demand_paging_test TEST_GEN_PROGS_s390x += dirty_log_test TEST_GEN_PROGS_s390x += kvm_create_max_vcpus +TEST_GEN_PROGS_s390x += mem_slot_test
TEST_GEN_PROGS += $(TEST_GEN_PROGS_$(UNAME_M)) LIBKVM += $(LIBKVM_$(UNAME_M)) diff --git a/tools/testing/selftests/kvm/mem_slot_test.c b/tools/testing/selftests/kvm/mem_slot_test.c new file mode 100644 index 000000000000..7c1009f0bc07 --- /dev/null +++ b/tools/testing/selftests/kvm/mem_slot_test.c @@ -0,0 +1,76 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * mem_slot_test + * + * Copyright (C) 2020, Red Hat, Inc. + * + * Test suite for memory region operations. + */ +#define _GNU_SOURCE /* for program_invocation_short_name */ +#include <linux/kvm.h> +#include <sys/mman.h> + +#include "test_util.h" +#include "kvm_util.h" + +/* + * Test it can be added memory slots up to KVM_CAP_NR_MEMSLOTS, then any + * tentative to add further slots should fail. + */ +static void test_add_max_slots(void) +{ + int ret; + struct kvm_vm *vm; + uint32_t max_mem_slots; + uint32_t slot; + uint64_t guest_addr; + uint64_t mem_reg_npages; + uint64_t mem_reg_size; + void *mem; + + max_mem_slots = kvm_check_cap(KVM_CAP_NR_MEMSLOTS); + TEST_ASSERT(max_mem_slots > 0, + "KVM_CAP_NR_MEMSLOTS should be greater than 0"); + pr_info("Allowed number of memory slots: %i\n", max_mem_slots); + + vm = vm_create(VM_MODE_DEFAULT, 0, O_RDWR); + + /* + * Uses 1MB sized/aligned memory region since this is the minimal + * required on s390x. + */ + mem_reg_size = 0x100000; + mem_reg_npages = vm_calc_num_guest_pages(VM_MODE_DEFAULT, mem_reg_size); + + guest_addr = 0x0; + + /* Check it can be added memory slots up to the maximum allowed */ + pr_info("Adding slots 0..%i, each memory region with %ldK size\n", + (max_mem_slots - 1), mem_reg_size >> 10); + for (slot = 0; slot < max_mem_slots; slot++) { + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, + guest_addr, slot, mem_reg_npages, + 0); + guest_addr += mem_reg_size; + } + + /* Check it cannot be added memory slots beyond the limit */ + mem = mmap(NULL, mem_reg_size, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + TEST_ASSERT(mem != MAP_FAILED, "Failed to mmap() host"); + + ret = ioctl(vm_get_fd(vm), KVM_SET_USER_MEMORY_REGION, + &(struct kvm_userspace_memory_region) {slot, 0, guest_addr, + mem_reg_size, (uint64_t) mem}); + TEST_ASSERT(ret == -1 && errno == EINVAL, + "Adding one more memory slot should fail with EINVAL"); + + munmap(mem, mem_reg_size); + kvm_vm_free(vm); +} + +int main(int argc, char *argv[]) +{ + test_add_max_slots(); + return 0; +}