Skip QEMU SPDM tests when QEMU lacks spdm_port support

Stock QEMU builds don't include NVMe SPDM support (the spdm_port
property). Probe QEMU via '-device nvme,help' and skip the test
when the property is absent, instead of failing with
"Property 'nvme.spdm_port' not found".

Author: xaionaro@dx.center

tests/qemu/go_go_test.go

@@ -17,6 +17,7 @@ import (
 func TestQEMU_GoRequester_GoResponder(t *testing.T) {
 	skipIfNoQEMU(t)
 	skipIfNoKernel(t)
+	skipIfNoSPDMSupport(t)
 
 	guestBin := buildGuestBinary(t)
 	initramfs := buildInitramfs(t, guestBin)

tests/qemu/go_ref_test.go

@@ -22,6 +22,7 @@ import (
 func TestQEMU_GoRequester_RefResponder(t *testing.T) {
 	skipIfNoQEMU(t)
 	skipIfNoKernel(t)
+	skipIfNoSPDMSupport(t)
 
 	emuBin := os.Getenv("SPDM_EMU_BIN")
 	if emuBin == "" {

tests/qemu/harness_test.go

@@ -174,3 +174,24 @@ func skipIfNoKernel(t *testing.T) {
 		t.Skipf("kernel not available: %v", err)
 	}
 }
+
+// skipIfNoSPDMSupport skips the test if QEMU lacks NVMe SPDM support
+// (the spdm_port property). Stock QEMU builds don't include this;
+// it requires an SPDM-patched QEMU.
+func skipIfNoSPDMSupport(t *testing.T) {
+	t.Helper()
+
+	qemuBin, err := findQEMU()
+	if err != nil {
+		t.Skipf("QEMU not available: %v", err)
+	}
+
+	out, err := exec.Command(qemuBin, "-device", "nvme,help").CombinedOutput()
+	if err != nil {
+		t.Skipf("failed to probe QEMU NVMe properties: %v", err)
+	}
+
+	if !strings.Contains(string(out), "spdm_port") {
+		t.Skip("QEMU NVMe device does not support spdm_port (SPDM-patched QEMU required)")
+	}
+}