diff options
Diffstat (limited to 'tools/testing/selftests/kvm/x86_64/xcr0_cpuid_test.c')
-rw-r--r-- | tools/testing/selftests/kvm/x86_64/xcr0_cpuid_test.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/x86_64/xcr0_cpuid_test.c b/tools/testing/selftests/kvm/x86_64/xcr0_cpuid_test.c new file mode 100644 index 0000000000..77d04a7bda --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/xcr0_cpuid_test.c @@ -0,0 +1,137 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * XCR0 cpuid test + * + * Copyright (C) 2022, Google LLC. + */ +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ioctl.h> + +#include "test_util.h" + +#include "kvm_util.h" +#include "processor.h" + +/* + * Assert that architectural dependency rules are satisfied, e.g. that AVX is + * supported if and only if SSE is supported. + */ +#define ASSERT_XFEATURE_DEPENDENCIES(supported_xcr0, xfeatures, dependencies) \ +do { \ + uint64_t __supported = (supported_xcr0) & ((xfeatures) | (dependencies)); \ + \ + __GUEST_ASSERT((__supported & (xfeatures)) != (xfeatures) || \ + __supported == ((xfeatures) | (dependencies)), \ + "supported = 0x%llx, xfeatures = 0x%llx, dependencies = 0x%llx", \ + __supported, (xfeatures), (dependencies)); \ +} while (0) + +/* + * Assert that KVM reports a sane, usable as-is XCR0. Architecturally, a CPU + * isn't strictly required to _support_ all XFeatures related to a feature, but + * at the same time XSETBV will #GP if bundled XFeatures aren't enabled and + * disabled coherently. E.g. a CPU can technically enumerate supported for + * XTILE_CFG but not XTILE_DATA, but attempting to enable XTILE_CFG without + * XTILE_DATA will #GP. + */ +#define ASSERT_ALL_OR_NONE_XFEATURE(supported_xcr0, xfeatures) \ +do { \ + uint64_t __supported = (supported_xcr0) & (xfeatures); \ + \ + __GUEST_ASSERT(!__supported || __supported == (xfeatures), \ + "supported = 0x%llx, xfeatures = 0x%llx", \ + __supported, (xfeatures)); \ +} while (0) + +static void guest_code(void) +{ + uint64_t xcr0_reset; + uint64_t supported_xcr0; + int i, vector; + + set_cr4(get_cr4() | X86_CR4_OSXSAVE); + + xcr0_reset = xgetbv(0); + supported_xcr0 = this_cpu_supported_xcr0(); + + GUEST_ASSERT(xcr0_reset == XFEATURE_MASK_FP); + + /* Check AVX */ + ASSERT_XFEATURE_DEPENDENCIES(supported_xcr0, + XFEATURE_MASK_YMM, + XFEATURE_MASK_SSE); + + /* Check MPX */ + ASSERT_ALL_OR_NONE_XFEATURE(supported_xcr0, + XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR); + + /* Check AVX-512 */ + ASSERT_XFEATURE_DEPENDENCIES(supported_xcr0, + XFEATURE_MASK_AVX512, + XFEATURE_MASK_SSE | XFEATURE_MASK_YMM); + ASSERT_ALL_OR_NONE_XFEATURE(supported_xcr0, + XFEATURE_MASK_AVX512); + + /* Check AMX */ + ASSERT_ALL_OR_NONE_XFEATURE(supported_xcr0, + XFEATURE_MASK_XTILE); + + vector = xsetbv_safe(0, supported_xcr0); + __GUEST_ASSERT(!vector, + "Expected success on XSETBV(0x%llx), got vector '0x%x'", + supported_xcr0, vector); + + for (i = 0; i < 64; i++) { + if (supported_xcr0 & BIT_ULL(i)) + continue; + + vector = xsetbv_safe(0, supported_xcr0 | BIT_ULL(i)); + __GUEST_ASSERT(vector == GP_VECTOR, + "Expected #GP on XSETBV(0x%llx), supported XCR0 = %llx, got vector '0x%x'", + BIT_ULL(i), supported_xcr0, vector); + } + + GUEST_DONE(); +} + +int main(int argc, char *argv[]) +{ + struct kvm_vcpu *vcpu; + struct kvm_run *run; + struct kvm_vm *vm; + struct ucall uc; + + TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XSAVE)); + + vm = vm_create_with_one_vcpu(&vcpu, guest_code); + run = vcpu->run; + + vm_init_descriptor_tables(vm); + vcpu_init_descriptor_tables(vcpu); + + while (1) { + vcpu_run(vcpu); + + TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, + "Unexpected exit reason: %u (%s),\n", + run->exit_reason, + exit_reason_str(run->exit_reason)); + + switch (get_ucall(vcpu, &uc)) { + case UCALL_ABORT: + REPORT_GUEST_ASSERT(uc); + break; + case UCALL_DONE: + goto done; + default: + TEST_FAIL("Unknown ucall %lu", uc.cmd); + } + } + +done: + kvm_vm_free(vm); + return 0; +} |