Introduce a new selftest for the KVM_GET_EMULATED_CPUID ioctl. Since the behavior and functionality is similar to get_cpuid_test, the test checks:
1) checks for corner case in the nent field of the struct kvm_cpuid2. 2) sets and gets it as cpuid from the guest VM
Signed-off-by: Emanuele Giuseppe Esposito eesposit@redhat.com --- tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/x86_64/get_emulated_cpuid.c | 198 ++++++++++++++++++ 3 files changed, 200 insertions(+) create mode 100644 tools/testing/selftests/kvm/x86_64/get_emulated_cpuid.c
diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore index 7bd7e776c266..f1523f3bfd04 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -8,6 +8,7 @@ /x86_64/debug_regs /x86_64/evmcs_test /x86_64/get_cpuid_test +x86_64/get_emulated_cpuid /x86_64/get_msr_index_features /x86_64/kvm_pv_test /x86_64/hyperv_clock diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 67eebb53235f..0d8d3bd5a7c7 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -40,6 +40,7 @@ LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_ha
TEST_GEN_PROGS_x86_64 = x86_64/cr4_cpuid_sync_test TEST_GEN_PROGS_x86_64 += x86_64/get_msr_index_features +TEST_GEN_PROGS_x86_64 += x86_64/get_emulated_cpuid TEST_GEN_PROGS_x86_64 += x86_64/evmcs_test TEST_GEN_PROGS_x86_64 += x86_64/get_cpuid_test TEST_GEN_PROGS_x86_64 += x86_64/hyperv_clock diff --git a/tools/testing/selftests/kvm/x86_64/get_emulated_cpuid.c b/tools/testing/selftests/kvm/x86_64/get_emulated_cpuid.c new file mode 100644 index 000000000000..79fdbf4a1df1 --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/get_emulated_cpuid.c @@ -0,0 +1,198 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2021, Red Hat Inc. + * + * Generic tests for KVM CPUID set/get ioctls + */ +#include <asm/kvm_para.h> +#include <linux/kvm_para.h> +#include <stdint.h> + +#include "test_util.h" +#include "kvm_util.h" +#include "processor.h" + +#define VCPU_ID 0 +#define MAX_NENT 1000 + +/* CPUIDs known to differ */ +struct { + u32 function; + u32 index; +} mangled_cpuids[] = { + {.function = 0xd, .index = 0}, +}; + +static void guest_main(void) +{ + +} + +static bool is_cpuid_mangled(struct kvm_cpuid_entry2 *entrie) +{ + int i; + + for (i = 0; i < sizeof(mangled_cpuids); i++) { + if (mangled_cpuids[i].function == entrie->function && + mangled_cpuids[i].index == entrie->index) + return true; + } + + return false; +} + +static void check_cpuid(struct kvm_cpuid2 *cpuid, struct kvm_cpuid_entry2 *entrie) +{ + int i; + + for (i = 0; i < cpuid->nent; i++) { + if (cpuid->entries[i].function == entrie->function && + cpuid->entries[i].index == entrie->index) { + if (is_cpuid_mangled(entrie)) + return; + + TEST_ASSERT(cpuid->entries[i].eax == entrie->eax && + cpuid->entries[i].ebx == entrie->ebx && + cpuid->entries[i].ecx == entrie->ecx && + cpuid->entries[i].edx == entrie->edx, + "CPUID 0x%x.%x differ: 0x%x:0x%x:0x%x:0x%x vs 0x%x:0x%x:0x%x:0x%x", + entrie->function, entrie->index, + cpuid->entries[i].eax, cpuid->entries[i].ebx, + cpuid->entries[i].ecx, cpuid->entries[i].edx, + entrie->eax, entrie->ebx, entrie->ecx, entrie->edx); + return; + } + } + + TEST_ASSERT(false, "CPUID 0x%x.%x not found", entrie->function, entrie->index); +} + +static void compare_cpuids(struct kvm_cpuid2 *cpuid1, + struct kvm_cpuid2 *cpuid2) +{ + int i; + + for (i = 0; i < cpuid1->nent; i++) + check_cpuid(cpuid2, &cpuid1->entries[i]); + + for (i = 0; i < cpuid2->nent; i++) + check_cpuid(cpuid1, &cpuid2->entries[i]); +} + +struct kvm_cpuid2 *vcpu_alloc_cpuid(struct kvm_vm *vm, vm_vaddr_t *p_gva, struct kvm_cpuid2 *cpuid) +{ + int size = sizeof(*cpuid) + cpuid->nent * sizeof(cpuid->entries[0]); + vm_vaddr_t gva = vm_vaddr_alloc(vm, size, + getpagesize(), 0, 0); + struct kvm_cpuid2 *guest_cpuids = addr_gva2hva(vm, gva); + + memcpy(guest_cpuids, cpuid, size); + + *p_gva = gva; + return guest_cpuids; +} + +static struct kvm_cpuid2 *alloc_custom_kvm_cpuid2(int nent) +{ + struct kvm_cpuid2 *cpuid; + size_t size; + + size = sizeof(*cpuid); + size += nent * sizeof(struct kvm_cpuid_entry2); + cpuid = calloc(1, size); + if (!cpuid) { + perror("malloc"); + abort(); + } + + cpuid->nent = nent; + + return cpuid; +} + +static void clean_entries_kvm_cpuid2(struct kvm_cpuid2 *cpuid, int nent) +{ + size_t size; + int old_nent; + + size = sizeof(*cpuid); + size += nent * sizeof(struct kvm_cpuid_entry2); + + old_nent = cpuid->nent; + memset(cpuid, 0, size); + cpuid->nent = old_nent; +} + +static void test_emulated_entries(struct kvm_vm *vm) +{ + int res, right_nent; + struct kvm_cpuid2 *cpuid; + + cpuid = alloc_custom_kvm_cpuid2(MAX_NENT); + + /* 0 nent, return E2BIG */ + cpuid->nent = 0; + res = _kvm_ioctl(vm, KVM_GET_EMULATED_CPUID, cpuid); + TEST_ASSERT(res == -1 && errno == E2BIG, + "KVM_GET_EMULATED_CPUID should fail E2BIG with nent=0"); + clean_entries_kvm_cpuid2(cpuid, MAX_NENT); + + /* high nent, set the entries and adjust */ + cpuid->nent = MAX_NENT; + res = _kvm_ioctl(vm, KVM_GET_EMULATED_CPUID, cpuid); + TEST_ASSERT(res == 0, + "KVM_GET_EMULATED_CPUID should not fail with nent > actual nent"); + right_nent = cpuid->nent; + clean_entries_kvm_cpuid2(cpuid, MAX_NENT); + + /* high nent, set the entries and adjust */ + cpuid->nent++; + res = _kvm_ioctl(vm, KVM_GET_EMULATED_CPUID, cpuid); + TEST_ASSERT(res == 0, + "KVM_GET_EMULATED_CPUID should not fail with nent > actual nent"); + TEST_ASSERT(right_nent == cpuid->nent, + "KVM_GET_EMULATED_CPUID nent should be always the same"); + clean_entries_kvm_cpuid2(cpuid, MAX_NENT); + + /* low nent, return E2BIG */ + if (right_nent > 1) { + cpuid->nent = 1; + res = _kvm_ioctl(vm, KVM_GET_EMULATED_CPUID, cpuid); + TEST_ASSERT(res == -1 && errno == E2BIG, + "KVM_GET_EMULATED_CPUID should fail with nent=1"); + clean_entries_kvm_cpuid2(cpuid, MAX_NENT); + } + + /* exact nent */ + cpuid->nent = right_nent; + res = _kvm_ioctl(vm, KVM_GET_EMULATED_CPUID, cpuid); + TEST_ASSERT(res == 0, + "KVM_GET_EMULATED_CPUID should not fail with nent == actual nent"); + TEST_ASSERT(cpuid->nent == right_nent, + "KVM_GET_EMULATED_CPUID should be invaried when nent is exact"); + clean_entries_kvm_cpuid2(cpuid, MAX_NENT); + + free(cpuid); +} + +int main(void) +{ + struct kvm_cpuid2 *emul_cpuid, *cpuid2; + struct kvm_vm *vm; + + if (!kvm_check_cap(KVM_CAP_EXT_EMUL_CPUID)) { + print_skip("KVM_GET_EMULATED_CPUID not available"); + return 0; + } + + vm = vm_create_default(VCPU_ID, 0, guest_main); + + emul_cpuid = kvm_get_emulated_cpuid(); + vcpu_set_cpuid(vm, VCPU_ID, emul_cpuid); + cpuid2 = vcpu_get_cpuid(vm, VCPU_ID); + + test_emulated_entries(vm); + compare_cpuids(emul_cpuid, cpuid2); + + kvm_vm_free(vm); +}