On 12/13/2023 4:46 AM, Sagi Shahar wrote:
The test verifies that the guest runs TDVMCALL<INSTRUCTION.HLT> and the
guest vCPU enters to the halted state.
Signed-off-by: Erdem Aktas <erdemaktas@xxxxxxxxxx>
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 | 2 +
.../selftests/kvm/lib/x86_64/tdx/tdx.c | 10 +++
.../selftests/kvm/x86_64/tdx_vm_tests.c | 78 +++++++++++++++++++
3 files changed, 90 insertions(+)
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 85ba6aab79a7..b18e39d20498 100644
--- a/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h
+++ b/tools/testing/selftests/kvm/include/x86_64/tdx/tdx.h
@@ -8,6 +8,7 @@
#define TDG_VP_VMCALL_GET_TD_VM_CALL_INFO 0x10000
#define TDG_VP_VMCALL_REPORT_FATAL_ERROR 0x10003
+#define TDG_VP_VMCALL_INSTRUCTION_HLT 12
#define TDG_VP_VMCALL_INSTRUCTION_IO 30
#define TDG_VP_VMCALL_INSTRUCTION_RDMSR 31
#define TDG_VP_VMCALL_INSTRUCTION_WRMSR 32
@@ -20,5 +21,6 @@ uint64_t tdg_vp_vmcall_get_td_vmcall_info(uint64_t *r11, uint64_t *r12,
uint64_t *r13, uint64_t *r14);
uint64_t tdg_vp_vmcall_instruction_rdmsr(uint64_t index, uint64_t *ret_value);
uint64_t tdg_vp_vmcall_instruction_wrmsr(uint64_t index, uint64_t value);
+uint64_t tdg_vp_vmcall_instruction_hlt(uint64_t interrupt_blocked_flag);
#endif // SELFTEST_TDX_TDX_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 88ea6f2a6469..9485bafedc38 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/tdx/tdx.c
@@ -114,3 +114,13 @@ uint64_t tdg_vp_vmcall_instruction_wrmsr(uint64_t index, uint64_t value)
return __tdx_hypercall(&args, 0);
}
+
+uint64_t tdg_vp_vmcall_instruction_hlt(uint64_t interrupt_blocked_flag)
+{
+ struct tdx_hypercall_args args = {
+ .r11 = TDG_VP_VMCALL_INSTRUCTION_HLT,
+ .r12 = interrupt_blocked_flag,
+ };
+
+ return __tdx_hypercall(&args, 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 5db3701cc6d9..5fae4c6e5f95 100644
--- a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
+++ b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c
@@ -721,6 +721,83 @@ void verify_guest_msr_writes(void)
printf("\t ... PASSED\n");
}
+/*
+ * Verifies HLT functionality.
+ */
+void guest_hlt(void)
+{
+ uint64_t ret;
+ uint64_t interrupt_blocked_flag;
+
+ interrupt_blocked_flag = 0;
+ ret = tdg_vp_vmcall_instruction_hlt(interrupt_blocked_flag);
+ if (ret)
+ tdx_test_fatal(ret);
+
+ tdx_test_success();
+}
+
+void _verify_guest_hlt(int signum);
+
+void wake_me(int interval)
+{
+ struct sigaction action;
+
+ action.sa_handler = _verify_guest_hlt;
+ sigemptyset(&action.sa_mask);
+ action.sa_flags = 0;
+
+ TEST_ASSERT(sigaction(SIGALRM, &action, NULL) == 0,
+ "Could not set the alarm handler!");
+
+ alarm(interval);
+}
+
+void _verify_guest_hlt(int signum)
+{
+ struct kvm_vm *vm;
+ static struct kvm_vcpu *vcpu;
+
+ /*
+ * This function will also be called by SIGALRM handler to check the
+ * vCPU MP State. If vm has been initialized, then we are in the signal
+ * handler. Check the MP state and let the guest run again.
+ */
+ if (vcpu != NULL) {
What if the following case if there is a bug in KVM so that:
In guest, execution of tdg_vp_vmcall_instruction_hlt() return 0, but the
vcpu is not actually halted. Then guest will call tdx_test_success().
And the first call of _verify_guest_hlt() will call kvm_vm_free(vm) to free
the vm, which also frees the vcpu, and 1 second later, in this path vcpu
will
be accessed after free.
+ struct kvm_mp_state mp_state;
+
+ vcpu_mp_state_get(vcpu, &mp_state);
+ TEST_ASSERT_EQ(mp_state.mp_state, KVM_MP_STATE_HALTED);
+
+ /* Let the guest to run and finish the test.*/
+ mp_state.mp_state = KVM_MP_STATE_RUNNABLE;
+ vcpu_mp_state_set(vcpu, &mp_state);
+ return;
+ }
+
+ vm = td_create();
+ td_initialize(vm, VM_MEM_SRC_ANONYMOUS, 0);
+ vcpu = td_vcpu_add(vm, 0, guest_hlt);
+ td_finalize(vm);
+
+ printf("Verifying HLT:\n");
+
+ printf("\t ... Running guest\n");
+
+ /* Wait 1 second for guest to execute HLT */
+ wake_me(1);
+ td_vcpu_run(vcpu);
+
+ TDX_TEST_ASSERT_SUCCESS(vcpu);
+
+ kvm_vm_free(vm);
+ printf("\t ... PASSED\n");
+}
+
+void verify_guest_hlt(void)
+{
+ _verify_guest_hlt(0);
+}
int main(int argc, char **argv)
{
@@ -740,6 +817,7 @@ int main(int argc, char **argv)
run_in_new_process(&verify_guest_reads);
run_in_new_process(&verify_guest_msr_writes);
run_in_new_process(&verify_guest_msr_reads);
+ run_in_new_process(&verify_guest_hlt);
return 0;
}
