Re: [RFC 4/5] selftests: KVM: SNP IOCTL test
From: Peter Gonda
Date: Thu Jul 11 2024 - 11:58:12 EST
On Wed, Jul 10, 2024 at 4:06 PM Pratik R. Sampat
<pratikrajesh.sampat@xxxxxxx> wrote:
>
> Introduce testing of SNP ioctl calls. This patch includes both positive
> and negative tests of various parameters such as flags, page types and
> policies.
>
> Signed-off-by: Pratik R. Sampat <pratikrajesh.sampat@xxxxxxx>
Tested-by: Peter Gonda <pgonda@xxxxxxxxxx>
> ---
> .../selftests/kvm/x86_64/sev_smoke_test.c | 119 +++++++++++++++++-
> 1 file changed, 118 insertions(+), 1 deletion(-)
>
> 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 500c67b3793b..1d5c275c11b3 100644
> --- a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c
> +++ b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c
> @@ -186,13 +186,130 @@ static void test_sev_launch(void *guest_code, uint32_t type, uint64_t policy)
> kvm_vm_free(vm);
> }
>
> +static int spawn_snp_launch_start(uint32_t type, uint64_t policy, uint8_t flags)
> +{
> + struct kvm_vcpu *vcpu;
> + struct kvm_vm *vm;
> + int ret;
> +
> + vm = vm_sev_create_with_one_vcpu(type, NULL, &vcpu);
> + ret = snp_vm_launch(vm, policy, flags);
> + kvm_vm_free(vm);
> +
> + return ret;
> +}
> +
> +static void test_snp_launch_start(uint32_t type, uint64_t policy)
> +{
> + uint8_t i;
> + int ret;
> +
> + ret = spawn_snp_launch_start(type, policy, 0);
> + TEST_ASSERT(!ret,
> + "KVM_SEV_SNP_LAUNCH_START should not fail, invalid flag.");
> +
> + for (i = 1; i < 8; i++) {
> + ret = spawn_snp_launch_start(type, policy, BIT(i));
> + TEST_ASSERT(ret && errno == EINVAL,
> + "KVM_SEV_SNP_LAUNCH_START should fail, invalid flag.");
> + }
To save readers sometime do we want to comment that flags must be zero?
> +
> + ret = spawn_snp_launch_start(type, 0, 0);
> + TEST_ASSERT(ret && errno == EINVAL,
> + "KVM_SEV_SNP_LAUNCH_START should fail, invalid policy.");
> +
> + ret = spawn_snp_launch_start(type, SNP_POLICY_SMT, 0);
> + TEST_ASSERT(ret && errno == EINVAL,
> + "KVM_SEV_SNP_LAUNCH_START should fail, invalid policy.");
> +
> + ret = spawn_snp_launch_start(type, SNP_POLICY_RSVD_MBO, 0);
> + TEST_ASSERT(ret && errno == EINVAL,
> + "KVM_SEV_SNP_LAUNCH_START should fail, invalid policy.");
Ditto on SMT comment, this could pass if SMT was disabled right?
> +
> + ret = spawn_snp_launch_start(type, SNP_POLICY_SMT | SNP_POLICY_RSVD_MBO |
> + (255 * SNP_POLICY_ABI_MAJOR) |
> + (255 * SNP_POLICY_ABI_MINOR), 0);
> + TEST_ASSERT(ret && errno == EIO,
> + "KVM_SEV_SNP_LAUNCH_START should fail, invalid version.");
> +}
> +
> +static void test_snp_launch_update(uint32_t type, uint64_t policy)
> +{
> + struct kvm_vcpu *vcpu;
> + struct kvm_vm *vm;
> + int ret;
> +
> + for (int pgtype = 0; pgtype <= KVM_SEV_SNP_PAGE_TYPE_CPUID; pgtype++) {
Do we want to test KVM_SEV_SNP_PAGE_TYPE_CPUID+1 to make sure that fails?
> + vm = vm_sev_create_with_one_vcpu(type, NULL, &vcpu);
> + snp_vm_launch(vm, policy, 0);
> + ret = snp_vm_launch_update(vm, pgtype);
> +
> + switch (pgtype) {
> + case KVM_SEV_SNP_PAGE_TYPE_NORMAL:
> + case KVM_SEV_SNP_PAGE_TYPE_ZERO:
> + case KVM_SEV_SNP_PAGE_TYPE_UNMEASURED:
> + case KVM_SEV_SNP_PAGE_TYPE_SECRETS:
> + TEST_ASSERT(!ret,
> + "KVM_SEV_SNP_LAUNCH_UPDATE should not fail, invalid Page type.");
Double negative maybe: "KVM_SEV_SNP_LAUNCH_UPDATE should succeed..."
> + break;
> + case KVM_SEV_SNP_PAGE_TYPE_CPUID:
> + TEST_ASSERT(ret && errno == EIO,
> + "KVM_SEV_SNP_LAUNCH_UPDATE should fail, invalid Page type.");
This is a valid page type right? But I think the error is from the ASP
due to the page being malformed for a CPUID page.
> + break;
> + default:
> + TEST_ASSERT(ret && errno == EINVAL,
> + "KVM_SEV_SNP_LAUNCH_UPDATE should fail, invalid Page type.");
> + }
> +
> + kvm_vm_free(vm);
> + }
> +}
> +
> +void test_snp_launch_finish(uint32_t type, uint64_t policy)
> +{
> + struct kvm_vcpu *vcpu;
> + struct kvm_vm *vm;
> + int ret;
> +
> + vm = vm_sev_create_with_one_vcpu(type, NULL, &vcpu);
> + snp_vm_launch(vm, policy, 0);
> + snp_vm_launch_update(vm, KVM_SEV_SNP_PAGE_TYPE_NORMAL);
> + ret = snp_vm_launch_finish(vm, 0);
> + TEST_ASSERT(!ret,
> + "KVM_SEV_SNP_LAUNCH_FINISH should not fail, invalid flag.");
Comment is wrong, maybe: "KVM_SEV_SNP_LAUNCH_FINISH should not fail."
> + kvm_vm_free(vm);
> +
> + for (int i = 1; i < 16; i++) {
> + vm = vm_sev_create_with_one_vcpu(type, NULL, &vcpu);
> + snp_vm_launch(vm, policy, 0);
> + snp_vm_launch_update(vm, KVM_SEV_SNP_PAGE_TYPE_NORMAL);
> + ret = snp_vm_launch_finish(vm, BIT(i));
> + TEST_ASSERT(ret && errno == EINVAL,
> + "KVM_SEV_SNP_LAUNCH_FINISH should fail, invalid flag.");
> + kvm_vm_free(vm);
To save readers sometime do we want to comment that flags must be zero?
> + }
> +}
> +
> +static void test_sev_ioctl(void *guest_code, uint32_t type, uint64_t policy)
> +{
> + if (type == KVM_X86_SNP_VM) {
> + test_snp_launch_start(type, policy);
> + test_snp_launch_update(type, policy);
> + test_snp_launch_finish(type, policy);
> +
> + return;
> + }
> +
> + test_sev_launch(guest_code, type, policy);
> +}
> +
> static void test_sev(void *guest_code, uint32_t type, uint64_t policy)
> {
> struct kvm_vcpu *vcpu;
> struct kvm_vm *vm;
> struct ucall uc;
>
> - test_sev_launch(guest_code, type, policy);
> + test_sev_ioctl(guest_code, type, policy);
>
> vm = vm_sev_create_with_one_vcpu(type, guest_code, &vcpu);
>
> --
> 2.34.1
>