[RFC PATCH v3 15/31] KVM: selftests: TDX: Add TDX IO reads test

Ackerley Tng
2023-01-21T00:18:27Z

From: Sagi Shahar <sagis@google.com>

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>
---
.../selftests/kvm/x86_64/tdx_vm_tests.c | 87 +++++++++++++++++++
1 file changed, 87 insertions(+)

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 ac23d1ad1e687..71aa4e5907a05 100644
--- a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
+++ b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
@@ -428,6 +428,92 @@ 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");
+
+ 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;
+
+ 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;
+
+ 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;
+
+ vcpu_run(vcpu);
+ ASSERT_EQ(vcpu->run->exit_reason, KVM_EXIT_SYSTEM_EVENT);
+ ASSERT_EQ(vcpu->run->system_event.data[1], TDG_VP_VMCALL_INVALID_OPERAND);
+
+ 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);
@@ -443,6 +529,7 @@ 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;
}
--
2.39.0.246.g2a6d74b583-goog