On Wed, Aug 13, 2025 at 5:58 AM Binbin Wu <binbin...@linux.intel.com> wrote:
>
>
>
> On 8/8/2025 4:16 AM, Sagi Shahar wrote:
> > The test checks report_fatal_error functionality.
> >
> > TD guest can use TDG.VP.VMCALL<ReportFatalError> to report the fatal error
> > it has experienced. TD guest is requesting a termination with the error
> > information that include 16 general-purpose registers.
>
> I think it's worth to mention that KVM converts
> TDG.VP.VMCALL<ReportFatalError>
> to KVM_EXIT_SYSTEM_EVENT with the type KVM_SYSTEM_EVENT_TDX_FATAL.
>
Done. Will get updated in the next version.
> >
> > Co-developed-by: Binbin Wu <binbin...@linux.intel.com>
> > Signed-off-by: Binbin Wu <binbin...@linux.intel.com>
> > Signed-off-by: Sagi Shahar <sa...@google.com>
> > ---
> > .../selftests/kvm/include/x86/tdx/tdx.h | 6 ++-
> > .../selftests/kvm/include/x86/tdx/tdx_util.h | 1 +
> > .../selftests/kvm/include/x86/tdx/test_util.h | 19 +++++++
> > tools/testing/selftests/kvm/lib/x86/tdx/tdx.c | 18 +++++++
> > .../selftests/kvm/lib/x86/tdx/tdx_util.c | 6 +++
> > .../selftests/kvm/lib/x86/tdx/test_util.c | 10 ++++
> > tools/testing/selftests/kvm/x86/tdx_vm_test.c | 51 ++++++++++++++++++-
> > 7 files changed, 108 insertions(+), 3 deletions(-)
> >
> > diff --git a/tools/testing/selftests/kvm/include/x86/tdx/tdx.h
> > b/tools/testing/selftests/kvm/include/x86/tdx/tdx.h
> > index a7161efe4ee2..2acccc9dccf9 100644
> > --- a/tools/testing/selftests/kvm/include/x86/tdx/tdx.h
> > +++ b/tools/testing/selftests/kvm/include/x86/tdx/tdx.h
> > @@ -4,9 +4,13 @@
> >
> > #include <stdint.h>
> >
> > +#include "kvm_util.h"
> > +
> > +#define TDG_VP_VMCALL_REPORT_FATAL_ERROR 0x10003
> > +
> > #define TDG_VP_VMCALL_INSTRUCTION_IO 30
> >
> > 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/tdx/tdx_util.h
> > b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
> > index 57a2f5893ffe..d66cf17f03ea 100644
> > --- a/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
> > +++ b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
> > @@ -15,5 +15,6 @@ 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/tdx/test_util.h
> > b/tools/testing/selftests/kvm/include/x86/tdx/test_util.h
> > index 07d63bf1ffe1..dafeee9af1dc 100644
> > --- a/tools/testing/selftests/kvm/include/x86/tdx/test_util.h
> > +++ b/tools/testing/selftests/kvm/include/x86/tdx/test_util.h
> > @@ -38,4 +38,23 @@ bool is_tdx_enabled(void);
> > void tdx_test_success(void);
> > void tdx_test_assert_success(struct kvm_vcpu *vcpu);
> >
> > +/*
> > + * 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.
>
> A according to the GHCI spec, this is the optional GPA pointing to a shared
> guest memory, but in these TDX KVM selftest cases, it may not used that way.
> It may need some clarification about it. And based on the usage in this patch
> series, the name data_gpa may be misleading.
>
I can add a comment at the call site saying that the data_gpa is a
fake one for the sake of testing. Whether the data_gpa points to a
valid shared memory or not doesn't make a lot of difference from a
unit test perspective since we are testing the ReportFatalError
functionality itself.
Making the data_gpa valid for the test requires setting up additional
shared memory with no significant benefit for the test.
>
> > + *
> > + * 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/tdx/tdx.c
> > b/tools/testing/selftests/kvm/lib/x86/tdx/tdx.c
> > index f417ee75bee2..ba088bfc1e62 100644
> > --- a/tools/testing/selftests/kvm/lib/x86/tdx/tdx.c
> > +++ b/tools/testing/selftests/kvm/lib/x86/tdx/tdx.c
> > @@ -1,5 +1,7 @@
> > // SPDX-License-Identifier: GPL-2.0-only
> >
> > +#include <string.h>
> > +
> > #include "tdx/tdcall.h"
> > #include "tdx/tdx.h"
> >
> > @@ -25,3 +27,19 @@ 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/tdx/tdx_util.c
> > b/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c
> > index e2bf9766dc03..5e4455be828a 100644
> > --- a/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c
> > +++ b/tools/testing/selftests/kvm/lib/x86/tdx/tdx_util.c
> > @@ -9,6 +9,7 @@
> > #include "kvm_util.h"
> > #include "processor.h"
> > #include "tdx/td_boot.h"
> > +#include "tdx/tdx.h"
> > #include "test_util.h"
> >
> > uint64_t tdx_s_bit;
> > @@ -603,3 +604,8 @@ void td_finalize(struct kvm_vm *vm)
> >
> > tdx_td_finalize_mr(vm);
> > }
> > +
> > +void td_vcpu_run(struct kvm_vcpu *vcpu)
> > +{
> > + vcpu_run(vcpu);
> > +}
> > diff --git a/tools/testing/selftests/kvm/lib/x86/tdx/test_util.c
> > b/tools/testing/selftests/kvm/lib/x86/tdx/test_util.c
> > index 7355b213c344..6c82a0c3bd37 100644
> > --- a/tools/testing/selftests/kvm/lib/x86/tdx/test_util.c
> > +++ b/tools/testing/selftests/kvm/lib/x86/tdx/test_util.c
> > @@ -59,3 +59,13 @@ void tdx_test_assert_success(struct kvm_vcpu *vcpu)
> > vcpu->run->io.port, vcpu->run->io.size,
> > vcpu->run->io.direction);
> > }
> > +
> > +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/tdx_vm_test.c
> > b/tools/testing/selftests/kvm/x86/tdx_vm_test.c
> > index fdb7c40065a6..7d6d71602761 100644
> > --- a/tools/testing/selftests/kvm/x86/tdx_vm_test.c
> > +++ b/tools/testing/selftests/kvm/x86/tdx_vm_test.c
> > @@ -3,6 +3,7 @@
> > #include <signal.h>
> >
> > #include "kvm_util.h"
> > +#include "tdx/tdx.h"
> > #include "tdx/tdx_util.h"
> > #include "tdx/test_util.h"
> > #include "test_util.h"
> > @@ -24,7 +25,51 @@ static void verify_td_lifecycle(void)
> >
> > printf("Verifying TD lifecycle:\n");
> >
> > - vcpu_run(vcpu);
> > + td_vcpu_run(vcpu);
> > + tdx_test_assert_success(vcpu);
> > +
> > + kvm_vm_free(vm);
> > + 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;
> > + tdx_test_fatal(err);
> > +
> > + tdx_test_success();
> > +}
> > +
> > +void verify_report_fatal_error(void)
> > +{
> > + struct kvm_vcpu *vcpu;
> > + struct kvm_vm *vm;
> > +
> > + 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.type,
> > KVM_SYSTEM_EVENT_TDX_FATAL);
> > + TEST_ASSERT_EQ(vcpu->run->system_event.ndata, 16);
> > +
> > + TEST_ASSERT_EQ(vcpu->run->system_event.data[12], 0x0BAAAAAD00000000);
> > + TEST_ASSERT_EQ(vcpu->run->system_event.data[13], 0);
> > +
> > + td_vcpu_run(vcpu);
> > tdx_test_assert_success(vcpu);
> >
> > kvm_vm_free(vm);
> > @@ -38,9 +83,11 @@ int main(int argc, char **argv)
> > if (!is_tdx_enabled())
> > ksft_exit_skip("TDX is not supported by the KVM. Exiting.\n");
> >
> > - ksft_set_plan(1);
> > + ksft_set_plan(2);
> > ksft_test_result(!run_in_new_process(&verify_td_lifecycle),
> > "verify_td_lifecycle\n");
> > + ksft_test_result(!run_in_new_process(&verify_report_fatal_error),
> > + "verify_report_fatal_error\n");
> >
> > ksft_finished();
> > return 0;
>
