[RFC PATCH v5 09/29] KVM: selftests: TDX: Add report_fatal_error test

From: Sagi Shahar
Date: Tue Dec 12 2023 - 15:47:46 EST


The test checks report_fatal_error functionality.

Signed-off-by: Sagi Shahar <sagis@xxxxxxxxxx>
Signed-off-by: Ackerley Tng <ackerleytng@xxxxxxxxxx>
Signed-off-by: Ryan Afranji <afranji@xxxxxxxxxx>
---
.../selftests/kvm/include/x86_64/tdx/tdx.h | 6 ++-
.../kvm/include/x86_64/tdx/tdx_util.h | 1 +
.../kvm/include/x86_64/tdx/test_util.h | 19 ++++++++
.../selftests/kvm/lib/x86_64/tdx/tdx.c | 39 ++++++++++++++++
.../selftests/kvm/lib/x86_64/tdx/tdx_util.c | 12 +++++
.../selftests/kvm/lib/x86_64/tdx/test_util.c | 10 +++++
.../selftests/kvm/x86_64/tdx_vm_tests.c | 45 +++++++++++++++++++
7 files changed, 131 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h
index a7161efe4ee2..1340c1070002 100644
--- a/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h
+++ b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h
@@ -3,10 +3,14 @@
#define SELFTEST_TDX_TDX_H

#include <stdint.h>
+#include "kvm_util_base.h"

-#define TDG_VP_VMCALL_INSTRUCTION_IO 30
+#define TDG_VP_VMCALL_REPORT_FATAL_ERROR 0x10003

+#define TDG_VP_VMCALL_INSTRUCTION_IO 30
+void handle_userspace_tdg_vp_vmcall_exit(struct kvm_vcpu *vcpu);
uint64_t tdg_vp_vmcall_instruction_io(uint64_t port, uint64_t size,
uint64_t write, uint64_t *data);
+void tdg_vp_vmcall_report_fatal_error(uint64_t error_code, uint64_t data_gpa);

#endif // SELFTEST_TDX_TDX_H
diff --git a/tools/testing/selftests/kvm/include/x86_64/tdx/tdx_util.h b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx_util.h
index 274b245f200b..32dd6b8fda46 100644
--- a/tools/testing/selftests/kvm/include/x86_64/tdx/tdx_util.h
+++ b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx_util.h
@@ -12,5 +12,6 @@ struct kvm_vm *td_create(void);
void td_initialize(struct kvm_vm *vm, enum vm_mem_backing_src_type src_type,
uint64_t attributes);
void td_finalize(struct kvm_vm *vm);
+void td_vcpu_run(struct kvm_vcpu *vcpu);

#endif // SELFTESTS_TDX_KVM_UTIL_H
diff --git a/tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h b/tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h
index b570b6d978ff..6d69921136bd 100644
--- a/tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h
+++ b/tools/testing/selftests/kvm/include/x86_64/tdx/test_util.h
@@ -49,4 +49,23 @@ bool is_tdx_enabled(void);
*/
void tdx_test_success(void);

+/**
+ * Report an error with @error_code to userspace.
+ *
+ * Return value from tdg_vp_vmcall_report_fatal_error is ignored since execution
+ * is not expected to continue beyond this point.
+ */
+void tdx_test_fatal(uint64_t error_code);
+
+/**
+ * Report an error with @error_code to userspace.
+ *
+ * @data_gpa may point to an optional shared guest memory holding the error
+ * string.
+ *
+ * Return value from tdg_vp_vmcall_report_fatal_error is ignored since execution
+ * is not expected to continue beyond this point.
+ */
+void tdx_test_fatal_with_data(uint64_t error_code, uint64_t data_gpa);
+
#endif // SELFTEST_TDX_TEST_UTIL_H
diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c
index c2414523487a..b854c3aa34ff 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c
@@ -1,8 +1,31 @@
// SPDX-License-Identifier: GPL-2.0-only

+#include <string.h>
+
#include "tdx/tdcall.h"
#include "tdx/tdx.h"

+void handle_userspace_tdg_vp_vmcall_exit(struct kvm_vcpu *vcpu)
+{
+ struct kvm_tdx_vmcall *vmcall_info = &vcpu->run->tdx.u.vmcall;
+ uint64_t vmcall_subfunction = vmcall_info->subfunction;
+
+ switch (vmcall_subfunction) {
+ case TDG_VP_VMCALL_REPORT_FATAL_ERROR:
+ vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
+ vcpu->run->system_event.ndata = 3;
+ vcpu->run->system_event.data[0] =
+ TDG_VP_VMCALL_REPORT_FATAL_ERROR;
+ vcpu->run->system_event.data[1] = vmcall_info->in_r12;
+ vcpu->run->system_event.data[2] = vmcall_info->in_r13;
+ vmcall_info->status_code = 0;
+ break;
+ default:
+ TEST_FAIL("TD VMCALL subfunction %lu is unsupported.\n",
+ vmcall_subfunction);
+ }
+}
+
uint64_t tdg_vp_vmcall_instruction_io(uint64_t port, uint64_t size,
uint64_t write, uint64_t *data)
{
@@ -25,3 +48,19 @@ uint64_t tdg_vp_vmcall_instruction_io(uint64_t port, uint64_t size,

return ret;
}
+
+void tdg_vp_vmcall_report_fatal_error(uint64_t error_code, uint64_t data_gpa)
+{
+ struct tdx_hypercall_args args;
+
+ memset(&args, 0, sizeof(struct tdx_hypercall_args));
+
+ if (data_gpa)
+ error_code |= 0x8000000000000000;
+
+ args.r11 = TDG_VP_VMCALL_REPORT_FATAL_ERROR;
+ args.r12 = error_code;
+ args.r13 = data_gpa;
+
+ __tdx_hypercall(&args, 0);
+}
diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c
index b302060049d5..d745bb6287c1 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx_util.c
@@ -10,6 +10,7 @@

#include "kvm_util.h"
#include "test_util.h"
+#include "tdx/tdx.h"
#include "tdx/td_boot.h"
#include "kvm_util_base.h"
#include "processor.h"
@@ -519,3 +520,14 @@ void td_finalize(struct kvm_vm *vm)

tdx_td_finalizemr(vm);
}
+
+void td_vcpu_run(struct kvm_vcpu *vcpu)
+{
+ vcpu_run(vcpu);
+
+ /* Handle TD VMCALLs that require userspace handling. */
+ if (vcpu->run->exit_reason == KVM_EXIT_TDX &&
+ vcpu->run->tdx.type == KVM_EXIT_TDX_VMCALL) {
+ handle_userspace_tdg_vp_vmcall_exit(vcpu);
+ }
+}
diff --git a/tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c b/tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c
index 6905d0ca3877..7f3cd8089cea 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/test_util.c
@@ -32,3 +32,13 @@ void tdx_test_success(void)
TDX_TEST_SUCCESS_SIZE,
TDG_VP_VMCALL_INSTRUCTION_IO_WRITE, &code);
}
+
+void tdx_test_fatal_with_data(uint64_t error_code, uint64_t data_gpa)
+{
+ tdg_vp_vmcall_report_fatal_error(error_code, data_gpa);
+}
+
+void tdx_test_fatal(uint64_t error_code)
+{
+ tdx_test_fatal_with_data(error_code, 0);
+}
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 a18d1c9d6026..8638c7bbedaa 100644
--- a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
+++ b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
@@ -2,6 +2,7 @@

#include <signal.h>
#include "kvm_util_base.h"
+#include "tdx/tdx.h"
#include "tdx/tdx_util.h"
#include "tdx/test_util.h"
#include "test_util.h"
@@ -30,6 +31,49 @@ void verify_td_lifecycle(void)
printf("\t ... PASSED\n");
}

+void guest_code_report_fatal_error(void)
+{
+ uint64_t err;
+
+ /*
+ * Note: err should follow the GHCI spec definition:
+ * bits 31:0 should be set to 0.
+ * bits 62:32 are used for TD-specific extended error code.
+ * bit 63 is used to mark additional information in shared memory.
+ */
+ err = 0x0BAAAAAD00000000;
+ if (err)
+ tdx_test_fatal(err);
+
+ tdx_test_success();
+}
+void verify_report_fatal_error(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_code_report_fatal_error);
+ td_finalize(vm);
+
+ printf("Verifying report_fatal_error:\n");
+
+ td_vcpu_run(vcpu);
+
+ TEST_ASSERT_EQ(vcpu->run->exit_reason, KVM_EXIT_SYSTEM_EVENT);
+ TEST_ASSERT_EQ(vcpu->run->system_event.ndata, 3);
+ TEST_ASSERT_EQ(vcpu->run->system_event.data[0], TDG_VP_VMCALL_REPORT_FATAL_ERROR);
+ TEST_ASSERT_EQ(vcpu->run->system_event.data[1], 0x0BAAAAAD00000000);
+ TEST_ASSERT_EQ(vcpu->run->system_event.data[2], 0);
+
+ 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);
@@ -40,6 +84,7 @@ int main(int argc, char **argv)
}

run_in_new_process(&verify_td_lifecycle);
+ run_in_new_process(&verify_report_fatal_error);

return 0;
}
--
2.43.0.472.g3155946c3a-goog