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

On 12/13/2023 4:46 AM, Sagi Shahar wrote:

The test checks report_fatal_error functionality.

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/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);
  

I find tdx_test_fatal() is called a lot and each call site checks the err before calling it. Is it simpler to move the check of err inside of tdx_test_fatal() so that the callers just call it without check it every time?

• 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; }