@@ -9,6 +9,9 @@
#define TDX_TEST_SUCCESS_PORT 0x30
#define TDX_TEST_SUCCESS_SIZE 4
+#define TDX_TEST_REPORT_PORT 0x31
+#define TDX_TEST_REPORT_SIZE 4
+
/**
* Assert that some IO operation involving tdg_vp_vmcall_instruction_io() was
* called in the guest.
@@ -102,4 +105,10 @@ void tdx_test_fatal(uint64_t error_code);
*/
void tdx_test_fatal_with_data(uint64_t error_code, uint64_t data_gpa);
+/**
+ * Report a 32 bit value from the guest to user space using TDG.VP.VMCALL
+ * <Instruction.IO> call. Data is reported on port TDX_TEST_REPORT_PORT.
+ */
+uint64_t tdx_test_report_to_user_space(uint32_t data);
+
#endif // SELFTEST_TDX_TEST_UTIL_H
@@ -42,3 +42,14 @@ void tdx_test_fatal(uint64_t error_code)
{
tdx_test_fatal_with_data(error_code, 0);
}
+
+uint64_t tdx_test_report_to_user_space(uint32_t data)
+{
+ /* Upcast data to match tdg_vp_vmcall_instruction_io signature */
+ uint64_t data_64 = data;
+
+ return tdg_vp_vmcall_instruction_io(TDX_TEST_REPORT_PORT,
+ TDX_TEST_REPORT_SIZE,
+ TDG_VP_VMCALL_INSTRUCTION_IO_WRITE,
+ &data_64);
+}
@@ -2,6 +2,7 @@
#include <signal.h>
#include "kvm_util_base.h"
+#include "processor.h"
#include "tdx/tdcall.h"
#include "tdx/tdx.h"
#include "tdx/tdx_util.h"
@@ -154,6 +155,110 @@ void verify_td_ioexit(void)
printf("\t ... PASSED\n");
}
+/*
+ * Verifies CPUID functionality by reading CPUID values in guest. The guest
+ * will then send the values to userspace using an IO write to be checked
+ * against the expected values.
+ */
+void guest_code_cpuid(void)
+{
+ uint64_t err;
+ uint32_t ebx, ecx;
+
+ /* Read CPUID leaf 0x1 */
+ asm volatile (
+ "cpuid"
+ : "=b" (ebx), "=c" (ecx)
+ : "a" (0x1)
+ : "edx");
+
+ err = tdx_test_report_to_user_space(ebx);
+ if (err)
+ tdx_test_fatal(err);
+
+ err = tdx_test_report_to_user_space(ecx);
+ if (err)
+ tdx_test_fatal(err);
+
+ tdx_test_success();
+}
+
+void verify_td_cpuid(void)
+{
+ struct kvm_vm *vm;
+ struct kvm_vcpu *vcpu;
+
+ uint32_t ebx, ecx;
+ const struct kvm_cpuid_entry2 *cpuid_entry;
+ uint32_t guest_clflush_line_size;
+ uint32_t guest_max_addressable_ids, host_max_addressable_ids;
+ uint32_t guest_sse3_enabled;
+ uint32_t guest_fma_enabled;
+ uint32_t guest_initial_apic_id;
+
+ vm = td_create();
+ td_initialize(vm, VM_MEM_SRC_ANONYMOUS, 0);
+ vcpu = td_vcpu_add(vm, 0, guest_code_cpuid);
+ td_finalize(vm);
+
+ printf("Verifying TD CPUID:\n");
+
+ /* Wait for guest to report ebx value */
+ vcpu_run(vcpu);
+ TDX_TEST_CHECK_GUEST_FAILURE(vcpu);
+ TDX_TEST_ASSERT_IO(vcpu, TDX_TEST_REPORT_PORT, 4,
+ TDG_VP_VMCALL_INSTRUCTION_IO_WRITE);
+ ebx = *(uint32_t *)((void *)vcpu->run + vcpu->run->io.data_offset);
+
+ /* Wait for guest to report either ecx value or error */
+ vcpu_run(vcpu);
+ TDX_TEST_CHECK_GUEST_FAILURE(vcpu);
+ TDX_TEST_ASSERT_IO(vcpu, TDX_TEST_REPORT_PORT, 4,
+ TDG_VP_VMCALL_INSTRUCTION_IO_WRITE);
+ ecx = *(uint32_t *)((void *)vcpu->run + vcpu->run->io.data_offset);
+
+ /* Wait for guest to complete execution */
+ vcpu_run(vcpu);
+ TDX_TEST_CHECK_GUEST_FAILURE(vcpu);
+ TDX_TEST_ASSERT_SUCCESS(vcpu);
+
+ /* Verify the CPUID values we got from the guest. */
+ printf("\t ... Verifying CPUID values from guest\n");
+
+ /* Get KVM CPUIDs for reference */
+ cpuid_entry = kvm_get_supported_cpuid_entry(1);
+ TEST_ASSERT(cpuid_entry, "CPUID entry missing\n");
+
+ host_max_addressable_ids = (cpuid_entry->ebx >> 16) & 0xFF;
+
+ guest_sse3_enabled = ecx & 0x1; // Native
+ guest_clflush_line_size = (ebx >> 8) & 0xFF; // Fixed
+ guest_max_addressable_ids = (ebx >> 16) & 0xFF; // As Configured
+ guest_fma_enabled = (ecx >> 12) & 0x1; // As Configured (if Native)
+ guest_initial_apic_id = (ebx >> 24) & 0xFF; // Calculated
+
+ ASSERT_EQ(guest_sse3_enabled, 1);
+ ASSERT_EQ(guest_clflush_line_size, 8);
+ ASSERT_EQ(guest_max_addressable_ids, host_max_addressable_ids);
+
+ /* TODO: This only tests the native value. To properly test
+ * "As Configured (if Native)" we need to override this value
+ * in the TD params
+ */
+ ASSERT_EQ(guest_fma_enabled, 1);
+
+ /* TODO: guest_initial_apic_id is calculated based on the number of
+ * VCPUs in the TD. From the spec: "Virtual CPU index, starting from 0
+ * and allocated sequentially on each successful TDH.VP.INIT"
+ * To test non-trivial values we either need a TD with multiple VCPUs
+ * or to pick a different calculated value.
+ */
+ ASSERT_EQ(guest_initial_apic_id, 0);
+
+ kvm_vm_free(vm);
+ printf("\t ... PASSED\n");
+}
+
int main(int argc, char **argv)
{
setbuf(stdout, NULL);
@@ -166,6 +271,7 @@ int main(int argc, char **argv)
run_in_new_process(&verify_td_lifecycle);
run_in_new_process(&verify_report_fatal_error);
run_in_new_process(&verify_td_ioexit);
+ run_in_new_process(&verify_td_cpuid);
return 0;
}