| Message ID | 20240709182936.146487-1-pgonda@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: selftests: Add SEV-ES shutdown test | expand |
Hi Peter, On 7/9/2024 1:29 PM, Peter Gonda wrote: > Regression test for ae20eef5 ("KVM: SVM: Update SEV-ES shutdown intercepts > with more metadata"). Test confirms userspace is correctly indicated of > a guest shutdown not previous behavior of an EINVAL from KVM_RUN. > > Cc: Paolo Bonzini <pbonzini@redhat.com> > Cc: Sean Christopherson <seanjc@google.com> > Cc: Alper Gun <alpergun@google.com> > Cc: Tom Lendacky <thomas.lendacky@amd.com> > Cc: Michael Roth <michael.roth@amd.com> > Cc: kvm@vger.kernel.org > Cc: linux-kselftest@vger.kernel.org > Signed-off-by: Peter Gonda <pgonda@google.com> Tested-by: Pratik R. Sampat <pratikrajesh.sampat@amd.com> > > --- > .../selftests/kvm/x86_64/sev_smoke_test.c | 26 +++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c > index 7c70c0da4fb74..04f24d5f09877 100644 > --- a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c > +++ b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c > @@ -160,6 +160,30 @@ static void test_sev(void *guest_code, uint64_t policy) > kvm_vm_free(vm); > } > > +static void guest_shutdown_code(void) > +{ > + __asm__ __volatile__("ud2"); > +} > + > +static void test_sev_es_shutdown(void) > +{ > + struct kvm_vcpu *vcpu; > + struct kvm_vm *vm; > + > + uint32_t type = KVM_X86_SEV_ES_VM; > + > + vm = vm_sev_create_with_one_vcpu(type, guest_shutdown_code, &vcpu); > + > + vm_sev_launch(vm, SEV_POLICY_ES, NULL); > + > + vcpu_run(vcpu); > + TEST_ASSERT(vcpu->run->exit_reason == KVM_EXIT_SHUTDOWN, > + "Wanted SHUTDOWN, got %s", > + exit_reason_str(vcpu->run->exit_reason)); > + > + kvm_vm_free(vm); > +} > + I guess this case also applies to SNP. So maybe once this patch is queued up I could spin another patch in my SNP kselftest patch series that parameterizes this function to test SNP as well. Thanks! Pratik > int main(int argc, char *argv[]) > { > TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SEV)); > @@ -171,6 +195,8 @@ int main(int argc, char *argv[]) > test_sev(guest_sev_es_code, SEV_POLICY_ES | SEV_POLICY_NO_DBG); > test_sev(guest_sev_es_code, SEV_POLICY_ES); > > + test_sev_es_shutdown(); > + > if (kvm_has_cap(KVM_CAP_XCRS) && > (xgetbv(0) & XFEATURE_MASK_X87_AVX) == XFEATURE_MASK_X87_AVX) { > test_sync_vmsa(0);
> > I guess this case also applies to SNP. So maybe once this patch is > queued up I could spin another patch in my SNP kselftest patch series > that parameterizes this function to test SNP as well. > Thanks! That sounds great. I plan on sending a few tests for the sev-es termination codes. I can base that on top of your SNP series.
On Tue, Jul 09, 2024, Peter Gonda wrote: > Regression test for ae20eef5 ("KVM: SVM: Update SEV-ES shutdown intercepts > with more metadata"). Test confirms userspace is correctly indicated of > a guest shutdown not previous behavior of an EINVAL from KVM_RUN. > > Cc: Paolo Bonzini <pbonzini@redhat.com> > Cc: Sean Christopherson <seanjc@google.com> > Cc: Alper Gun <alpergun@google.com> > Cc: Tom Lendacky <thomas.lendacky@amd.com> > Cc: Michael Roth <michael.roth@amd.com> > Cc: kvm@vger.kernel.org > Cc: linux-kselftest@vger.kernel.org > Signed-off-by: Peter Gonda <pgonda@google.com> > > --- > .../selftests/kvm/x86_64/sev_smoke_test.c | 26 +++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c > index 7c70c0da4fb74..04f24d5f09877 100644 > --- a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c > +++ b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c > @@ -160,6 +160,30 @@ static void test_sev(void *guest_code, uint64_t policy) > kvm_vm_free(vm); > } > > +static void guest_shutdown_code(void) > +{ > + __asm__ __volatile__("ud2"); Heh, this passes by dumb luck, not because the #UD itself causes a SHUTDOWN. It _looks_ like the #UD causes a shutdown, because KVM will always see the original guest RIP, but the shutdown actually occurs somewhere in the ucall_assert() in route_exception(). Now that x86 selftests install an IDT and exception handlers by default, it's actually quite hard to induce shutdown. Ok, not "hard", but it requires more work than simply generating a #UD. I'll add this as fixup when applying: diff --git a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c index 04f24d5f0987..2e9197eb1652 100644 --- a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c +++ b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c @@ -162,6 +162,12 @@ static void test_sev(void *guest_code, uint64_t policy) static void guest_shutdown_code(void) { + struct desc_ptr idt; + + /* Clobber the IDT so that #UD is guaranteed to trigger SHUTDOWN. */ + memset(&idt, 0, sizeof(idt)); + __asm__ __volatile__("lidt %0" :: "m"(idt)); + __asm__ __volatile__("ud2"); }
On Tue, 09 Jul 2024 11:29:36 -0700, Peter Gonda wrote: > Regression test for ae20eef5 ("KVM: SVM: Update SEV-ES shutdown intercepts > with more metadata"). Test confirms userspace is correctly indicated of > a guest shutdown not previous behavior of an EINVAL from KVM_RUN. Applied to kvm-x86 selftests, with the IDT clobbering. Thanks! [1/1] KVM: selftests: Add SEV-ES shutdown test https://github.com/kvm-x86/linux/commit/2f6fcfa1f426 -- https://github.com/kvm-x86/linux/tree/next
diff --git a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c index 7c70c0da4fb74..04f24d5f09877 100644 --- a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c +++ b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c @@ -160,6 +160,30 @@ static void test_sev(void *guest_code, uint64_t policy) kvm_vm_free(vm); } +static void guest_shutdown_code(void) +{ + __asm__ __volatile__("ud2"); +} + +static void test_sev_es_shutdown(void) +{ + struct kvm_vcpu *vcpu; + struct kvm_vm *vm; + + uint32_t type = KVM_X86_SEV_ES_VM; + + vm = vm_sev_create_with_one_vcpu(type, guest_shutdown_code, &vcpu); + + vm_sev_launch(vm, SEV_POLICY_ES, NULL); + + vcpu_run(vcpu); + TEST_ASSERT(vcpu->run->exit_reason == KVM_EXIT_SHUTDOWN, + "Wanted SHUTDOWN, got %s", + exit_reason_str(vcpu->run->exit_reason)); + + kvm_vm_free(vm); +} + int main(int argc, char *argv[]) { TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SEV)); @@ -171,6 +195,8 @@ int main(int argc, char *argv[]) test_sev(guest_sev_es_code, SEV_POLICY_ES | SEV_POLICY_NO_DBG); test_sev(guest_sev_es_code, SEV_POLICY_ES); + test_sev_es_shutdown(); + if (kvm_has_cap(KVM_CAP_XCRS) && (xgetbv(0) & XFEATURE_MASK_X87_AVX) == XFEATURE_MASK_X87_AVX) { test_sync_vmsa(0);
Regression test for ae20eef5 ("KVM: SVM: Update SEV-ES shutdown intercepts with more metadata"). Test confirms userspace is correctly indicated of a guest shutdown not previous behavior of an EINVAL from KVM_RUN. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Alper Gun <alpergun@google.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Michael Roth <michael.roth@amd.com> Cc: kvm@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Signed-off-by: Peter Gonda <pgonda@google.com> --- .../selftests/kvm/x86_64/sev_smoke_test.c | 26 +++++++++++++++++++ 1 file changed, 26 insertions(+)