Re: [RFC PATCH v5 14/29] KVM: selftests: TDX: Add TDX IO reads test

[Binbin Wu <binbin.wu@linux.intel.com>]

On 12/13/2023 4:46 AM, Sagi Shahar wrote:
> The test verifies IO reads of various sizes from the host to the guest.
>
> Signed-off-by: Sagi Shahar <sagis@google.com>
> Signed-off-by: Ackerley Tng <ackerleytng@google.com>
> Signed-off-by: Ryan Afranji <afranji@google.com>
> ---
>   .../selftests/kvm/x86_64/tdx_vm_tests.c       | 87 +++++++++++++++++++
>   1 file changed, 87 insertions(+)

Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>

>
> diff --git a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
> index a2b3e1aef151..699cba36e9ce 100644
> --- a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
> +++ b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
> @@ -429,6 +429,92 @@ void verify_guest_writes(void)
>   	printf("\t ... PASSED\n");
>   }
>   
> +#define TDX_IO_READS_TEST_PORT 0x52
> +
> +/*
> + * Verifies IO functionality by reading values of different sizes
> + * from the host.
> + */
> +void guest_io_reads(void)
> +{
> +	uint64_t data;
> +	uint64_t ret;
> +
> +	ret = tdg_vp_vmcall_instruction_io(TDX_IO_READS_TEST_PORT, 1,
> +					TDG_VP_VMCALL_INSTRUCTION_IO_READ,
> +					&data);
> +	if (ret)
> +		tdx_test_fatal(ret);
> +	if (data != 0xAB)
> +		tdx_test_fatal(1);
> +
> +	ret = tdg_vp_vmcall_instruction_io(TDX_IO_READS_TEST_PORT, 2,
> +					TDG_VP_VMCALL_INSTRUCTION_IO_READ,
> +					&data);
> +	if (ret)
> +		tdx_test_fatal(ret);
> +	if (data != 0xABCD)
> +		tdx_test_fatal(2);
> +
> +	ret = tdg_vp_vmcall_instruction_io(TDX_IO_READS_TEST_PORT, 4,
> +					TDG_VP_VMCALL_INSTRUCTION_IO_READ,
> +					&data);
> +	if (ret)
> +		tdx_test_fatal(ret);
> +	if (data != 0xFFABCDEF)
> +		tdx_test_fatal(4);
> +
> +	// Read an invalid number of bytes.
> +	ret = tdg_vp_vmcall_instruction_io(TDX_IO_READS_TEST_PORT, 5,
> +					TDG_VP_VMCALL_INSTRUCTION_IO_READ,
> +					&data);
> +	if (ret)
> +		tdx_test_fatal(ret);
> +
> +	tdx_test_success();
> +}
> +
> +void verify_guest_reads(void)
> +{
> +	struct kvm_vm *vm;
> +	struct kvm_vcpu *vcpu;
> +
> +	vm = td_create();
> +	td_initialize(vm, VM_MEM_SRC_ANONYMOUS, 0);
> +	vcpu = td_vcpu_add(vm, 0, guest_io_reads);
> +	td_finalize(vm);
> +
> +	printf("Verifying guest reads:\n");
> +
> +	td_vcpu_run(vcpu);
> +	TDX_TEST_CHECK_GUEST_FAILURE(vcpu);
> +	TDX_TEST_ASSERT_IO(vcpu, TDX_IO_READS_TEST_PORT, 1,
> +			TDG_VP_VMCALL_INSTRUCTION_IO_READ);
> +	*(uint8_t *)((void *)vcpu->run + vcpu->run->io.data_offset) = 0xAB;
> +
> +	td_vcpu_run(vcpu);
> +	TDX_TEST_CHECK_GUEST_FAILURE(vcpu);
> +	TDX_TEST_ASSERT_IO(vcpu, TDX_IO_READS_TEST_PORT, 2,
> +			TDG_VP_VMCALL_INSTRUCTION_IO_READ);
> +	*(uint16_t *)((void *)vcpu->run + vcpu->run->io.data_offset) = 0xABCD;
> +
> +	td_vcpu_run(vcpu);
> +	TDX_TEST_CHECK_GUEST_FAILURE(vcpu);
> +	TDX_TEST_ASSERT_IO(vcpu, TDX_IO_READS_TEST_PORT, 4,
> +			TDG_VP_VMCALL_INSTRUCTION_IO_READ);
> +	*(uint32_t *)((void *)vcpu->run + vcpu->run->io.data_offset) = 0xFFABCDEF;
> +
> +	td_vcpu_run(vcpu);
> +	TEST_ASSERT_EQ(vcpu->run->exit_reason, KVM_EXIT_SYSTEM_EVENT);
> +	TEST_ASSERT_EQ(vcpu->run->system_event.data[1], TDG_VP_VMCALL_INVALID_OPERAND);
> +
> +	td_vcpu_run(vcpu);
> +	TDX_TEST_ASSERT_SUCCESS(vcpu);
> +
> +	kvm_vm_free(vm);
> +	printf("\t ... PASSED\n");
> +}
> +
>   int main(int argc, char **argv)
>   {
>   	setbuf(stdout, NULL);
> @@ -444,6 +530,7 @@ int main(int argc, char **argv)
>   	run_in_new_process(&verify_td_cpuid);
>   	run_in_new_process(&verify_get_td_vmcall_info);
>   	run_in_new_process(&verify_guest_writes);
> +	run_in_new_process(&verify_guest_reads);
>   
>   	return 0;
>   }