[PATCH v12 05/23] KVM: selftests: Update kvm_init_vm_address_properties() for TDX

Sagi Shahar
2025-10-28T21:21:01Z

From: Isaku Yamahata <isaku.yamahata@intel.com>

Let kvm_init_vm_address_properties() initialize vm->arch.{s_bit, tag_mask}
similar to SEV.

TDX sets the shared bit based on the guest physical address width and
currently supports 48 and 52 widths.

Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Co-developed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Co-developed-by: Sagi Shahar <sagis@google.com>
Signed-off-by: Sagi Shahar <sagis@google.com>
---
.../selftests/kvm/include/x86/tdx/tdx_util.h | 14 ++++++++++++++
tools/testing/selftests/kvm/lib/x86/processor.c | 12 ++++++++++--
2 files changed, 24 insertions(+), 2 deletions(-)
create mode 100644 tools/testing/selftests/kvm/include/x86/tdx/tdx_util.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
new file mode 100644
index 000000000000..286d5e3c24b1
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/x86/tdx/tdx_util.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef SELFTESTS_TDX_TDX_UTIL_H
+#define SELFTESTS_TDX_TDX_UTIL_H
+
+#include <stdbool.h>
+
+#include "kvm_util.h"
+
+static inline bool is_tdx_vm(struct kvm_vm *vm)
+{
+ return vm->type == KVM_X86_TDX_VM;
+}
+
+#endif // SELFTESTS_TDX_TDX_UTIL_H
diff --git a/tools/testing/selftests/kvm/lib/x86/processor.c b/tools/testing/selftests/kvm/lib/x86/processor.c
index 2898fe4f6de4..519d60a3827c 100644
--- a/tools/testing/selftests/kvm/lib/x86/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86/processor.c
@@ -9,6 +9,7 @@
#include "pmu.h"
#include "processor.h"
#include "sev.h"
+#include "tdx/tdx_util.h"

#ifndef NUM_INTERRUPTS
#define NUM_INTERRUPTS 256
@@ -1195,12 +1196,19 @@ void kvm_get_cpu_address_width(unsigned int *pa_bits, unsigned int *va_bits)

void kvm_init_vm_address_properties(struct kvm_vm *vm)
{
+ uint32_t gpa_bits = kvm_cpu_property(X86_PROPERTY_GUEST_MAX_PHY_ADDR);
+
+ vm->arch.sev_fd = -1;
+
if (is_sev_vm(vm)) {
vm->arch.sev_fd = open_sev_dev_path_or_exit();
vm->arch.c_bit = BIT_ULL(this_cpu_property(X86_PROPERTY_SEV_C_BIT));
vm->gpa_tag_mask = vm->arch.c_bit;
- } else {
- vm->arch.sev_fd = -1;
+ } else if (is_tdx_vm(vm)) {
+ TEST_ASSERT(gpa_bits == 48 || gpa_bits == 52,
+ "TDX: bad X86_PROPERTY_GUEST_MAX_PHY_ADDR value: %u", gpa_bits);
+ vm->arch.s_bit = BIT_ULL(gpa_bits - 1);
+ vm->gpa_tag_mask = vm->arch.s_bit;
}
}

--
2.51.1.851.g4ebd6896fd-goog