diff options
| -rw-r--r-- | tools/testing/selftests/kvm/x86/msrs_test.c | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/tools/testing/selftests/kvm/x86/msrs_test.c b/tools/testing/selftests/kvm/x86/msrs_test.c index 1efaebb986c4..ec94c70b3f06 100644 --- a/tools/testing/selftests/kvm/x86/msrs_test.c +++ b/tools/testing/selftests/kvm/x86/msrs_test.c @@ -303,12 +303,17 @@ static void test_msrs(void) MSR_TEST(MSR_IA32_PL3_SSP, canonical_val, canonical_val | 1, SHSTK), }; + const struct kvm_x86_cpu_feature feat_none = X86_FEATURE_NONE; + const struct kvm_x86_cpu_feature feat_lm = X86_FEATURE_LM; + /* - * Create two vCPUs, but run them on the same task, to validate KVM's + * Create three vCPUs, but run them on the same task, to validate KVM's * context switching of MSR state. Don't pin the task to a pCPU to - * also validate KVM's handling of cross-pCPU migration. + * also validate KVM's handling of cross-pCPU migration. Use the full + * set of features for the first two vCPUs, but clear all features in + * third vCPU in order to test both positive and negative paths. */ - const int NR_VCPUS = 2; + const int NR_VCPUS = 3; struct kvm_vcpu *vcpus[NR_VCPUS]; struct kvm_vm *vm; @@ -323,6 +328,23 @@ static void test_msrs(void) sync_global_to_guest(vm, msrs); sync_global_to_guest(vm, ignore_unsupported_msrs); + /* + * Clear features in the "unsupported features" vCPU. This needs to be + * done before the first vCPU run as KVM's ABI is that guest CPUID is + * immutable once the vCPU has been run. + */ + for (idx = 0; idx < ARRAY_SIZE(__msrs); idx++) { + /* + * Don't clear LM; selftests are 64-bit only, and KVM doesn't + * honor LM=0 for MSRs that are supposed to exist if and only + * if the vCPU is a 64-bit model. Ditto for NONE; clearing a + * fake feature flag will result in false failures. + */ + if (memcmp(&msrs[idx].feature, &feat_lm, sizeof(feat_lm)) && + memcmp(&msrs[idx].feature, &feat_none, sizeof(feat_none))) + vcpu_clear_cpuid_feature(vcpus[2], msrs[idx].feature); + } + for (idx = 0; idx < ARRAY_SIZE(__msrs); idx++) { sync_global_to_guest(vm, idx); |