From: David Woodhouse Date: Mon, 20 Jul 2026 11:03:03 +0000 (+0100) Subject: KVM: selftests: sev_init2_tests: Derive SEV availability from KVM X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=f148dd411d451e3e4bf79240faec736d101832d4;p=thirdparty%2Flinux.git KVM: selftests: sev_init2_tests: Derive SEV availability from KVM The test asserted that the X86_FEATURE_SEV CPUID bit exactly matches whether KVM offers KVM_X86_SEV_VM. That is not an invariant: when all SEV ASIDs are assigned to SEV-SNP, KVM does not offer the SEV VM type even though CPUID reports SEV, so the test aborts on an SNP-only host. Derive SEV availability from KVM_CAP_VM_TYPES (as already done for SEV-ES and SNP), assert only the one-way implication that a type offered by KVM is also reported in CPUID, and TEST_REQUIRE() the SEV VM type so the test skips cleanly when it is unavailable. Reviewed-by: Tycho Andersen (AMD) Signed-off-by: David Woodhouse Message-ID: <5d3c345113748f39b7982e365d241abaf3e11086.1784545391.git.dwmw@amazon.co.uk> Signed-off-by: Paolo Bonzini --- diff --git a/tools/testing/selftests/kvm/x86/sev_init2_tests.c b/tools/testing/selftests/kvm/x86/sev_init2_tests.c index 8db88c355f16..689390c10f7c 100644 --- a/tools/testing/selftests/kvm/x86/sev_init2_tests.c +++ b/tools/testing/selftests/kvm/x86/sev_init2_tests.c @@ -130,12 +130,18 @@ int main(int argc, char *argv[]) KVM_X86_SEV_VMSA_FEATURES, &supported_vmsa_features); - have_sev = kvm_cpu_has(X86_FEATURE_SEV); - TEST_ASSERT(have_sev == !!(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SEV_VM)), - "sev: KVM_CAP_VM_TYPES (%x) does not match cpuid (checking %x)", - kvm_check_cap(KVM_CAP_VM_TYPES), 1 << KVM_X86_SEV_VM); + /* + * Whether a VM type is available depends on KVM, not just CPUID: e.g. + * when all SEV ASIDs are assigned to SEV-SNP, KVM does not offer the + * SEV VM type even though X86_FEATURE_SEV is set. Derive availability + * from KVM_CAP_VM_TYPES and only assert the one-way implication that a + * type offered by KVM must also be reported in CPUID. + */ + have_sev = kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SEV_VM); + TEST_ASSERT(!have_sev || kvm_cpu_has(X86_FEATURE_SEV), + "sev: SEV_VM supported without SEV in CPUID"); - TEST_REQUIRE(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SEV_VM)); + TEST_REQUIRE(have_sev); have_sev_es = kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(KVM_X86_SEV_ES_VM); TEST_ASSERT(!have_sev_es || kvm_cpu_has(X86_FEATURE_SEV_ES),