fix(collector): stop NVIDIA enrichment from clobbering PCIe status

enrichPCIeWithNVIDIAData unconditionally overwrote dev.Status after
collectPCIe() had already flagged a Warning/Critical (e.g. PCIe link
speed degraded), so a clean ECC/remap/reset readout silently downgraded
that finding back to OK while leaving the stale ErrorDescription behind.

Add a severity-ordered merge (OK/Unknown < Warning < Critical) shared
via mergeDeviceStatus in contract.go, and route both the NVIDIA status
calculation and the driver-unavailable fallback through it.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

audit/internal/collector/contract.go

@@ -1,6 +1,9 @@
 package collector
 
-import "strings"
+import (
+	"bee/audit/internal/schema"
+	"strings"
+)
 
 const (
 	statusOK       = "OK"
@@ -62,3 +65,43 @@ func isRAIDClass(class string) bool {
 		return false
 	}
 }
+
+// statusSeverity ranks component statuses so merges can only escalate, never
+// downgrade. Unknown ranks with OK: it means "couldn't tell", not "healthy",
+// so it must not silently clear a Warning/Critical raised by an earlier stage.
+func statusSeverity(status string) int {
+	switch strings.TrimSpace(status) {
+	case statusCritical:
+		return 3
+	case statusWarning:
+		return 2
+	case statusOK:
+		return 1
+	case statusUnknown:
+		return 1
+	default:
+		return 0
+	}
+}
+
+// mergeDeviceStatus applies status/description to dev only if it is at least
+// as severe as whatever is already set. This lets later enrichment stages
+// (e.g. NVIDIA telemetry) report their own findings without silently
+// clobbering a Warning/Critical raised earlier in the collector pipeline
+// (e.g. a PCIe link-speed degradation).
+func mergeDeviceStatus(dev *schema.HardwarePCIeDevice, status, description string) {
+	if dev == nil || status == "" {
+		return
+	}
+	current := ""
+	if dev.Status != nil {
+		current = strings.TrimSpace(*dev.Status)
+	}
+	if current != "" && current != statusUnknown && statusSeverity(status) <= statusSeverity(current) {
+		return
+	}
+	dev.Status = &status
+	if strings.TrimSpace(description) != "" {
+		dev.ErrorDescription = &description
+	}
+}

audit/internal/collector/nvidia.go

@@ -88,23 +88,24 @@ func enrichPCIeWithNVIDIAData(devs []schema.HardwarePCIeDevice, gpuByBDF map[str
 		}
 
 		status := statusOK
+		desc := ""
 		if info.ECCUncorrected != nil && *info.ECCUncorrected > 0 {
 			status = statusWarning
-			devs[i].ErrorDescription = stringPtr("GPU reports uncorrected ECC errors")
+			desc = "GPU reports uncorrected ECC errors"
 		}
 		if info.RemapUncorrectable != nil && *info.RemapUncorrectable > 0 {
 			status = statusWarning
-			devs[i].ErrorDescription = stringPtr("GPU has uncorrectable row remap events (bad HBM cell repair scheduled)")
+			desc = "GPU has uncorrectable row remap events (bad HBM cell repair scheduled)"
 		}
 		if info.RemapFailure != nil && *info.RemapFailure {
 			status = statusCritical
-			devs[i].ErrorDescription = stringPtr("GPU row remap failed to commit to InfoROM (XID 64)")
+			desc = "GPU row remap failed to commit to InfoROM (XID 64)"
 		}
 		if info.ResetRequired != nil && *info.ResetRequired {
 			status = statusCritical
-			devs[i].ErrorDescription = stringPtr("GPU requires a reset")
+			desc = "GPU requires a reset"
 		}
-		devs[i].Status = &status
+		mergeDeviceStatus(&devs[i], status, desc)
 		injectNVIDIATelemetry(&devs[i], info)
 		enriched++
 	}
@@ -326,8 +327,7 @@ func isNVIDIADevice(dev schema.HardwarePCIeDevice) bool {
 }
 
 func setPCIeFallback(dev *schema.HardwarePCIeDevice) {
-	status := statusUnknown
+	mergeDeviceStatus(dev, statusUnknown, "")
-	dev.Status = &status
 }
 
 func injectNVIDIATelemetry(dev *schema.HardwarePCIeDevice, info nvidiaGPUInfo) {

audit/internal/collector/nvidia_test.go

@@ -192,6 +192,108 @@ func TestEnrichPCIeWithNVIDIAData_remapFailureCritical(t *testing.T) {
 	}
 }
 
+func TestEnrichPCIeWithNVIDIAData_preservesExistingPCIeLinkWarning(t *testing.T) {
+	vendorID := NvidiaVendorID
+	bdf := "0000:65:00.0"
+	status := statusWarning
+	desc := "PCIe link speed degraded: running at Gen1, capable of Gen4"
+	devices := []schema.HardwarePCIeDevice{
+		{
+			HardwareComponentStatus: schema.HardwareComponentStatus{Status: &status, ErrorDescription: &desc},
+			VendorID:                &vendorID,
+			BDF:                     &bdf,
+		},
+	}
+
+	// Clean ECC/remap/reset: NVIDIA enrichment itself sees nothing wrong.
+	byBDF := map[string]nvidiaGPUInfo{
+		"0000:65:00.0": {},
+	}
+
+	out := enrichPCIeWithNVIDIAData(devices, byBDF, true)
+	if out[0].Status == nil || *out[0].Status != statusWarning {
+		t.Fatalf("status: got %v, want %v (must not be overwritten by clean NVIDIA telemetry)", out[0].Status, statusWarning)
+	}
+	if out[0].ErrorDescription == nil || *out[0].ErrorDescription != desc {
+		t.Fatalf("error_description: got %v, want %q", out[0].ErrorDescription, desc)
+	}
+}
+
+func TestEnrichPCIeWithNVIDIAData_eccWarningDoesNotDowngradeExistingWarning(t *testing.T) {
+	vendorID := NvidiaVendorID
+	bdf := "0000:65:00.0"
+	status := statusWarning
+	desc := "PCIe link speed degraded: running at Gen1, capable of Gen4"
+	devices := []schema.HardwarePCIeDevice{
+		{
+			HardwareComponentStatus: schema.HardwareComponentStatus{Status: &status, ErrorDescription: &desc},
+			VendorID:                &vendorID,
+			BDF:                     &bdf,
+		},
+	}
+
+	byBDF := map[string]nvidiaGPUInfo{
+		"0000:65:00.0": {ECCUncorrected: ptrInt64(1)},
+	}
+
+	out := enrichPCIeWithNVIDIAData(devices, byBDF, true)
+	// ECCUncorrected only raises Warning (same severity as the pre-existing
+	// PCIe-link Warning), so the merge must not lose the already-detected
+	// (and equally severe) status/description.
+	if out[0].Status == nil || *out[0].Status != statusWarning {
+		t.Fatalf("status: got %v, want %v", out[0].Status, statusWarning)
+	}
+	if out[0].ErrorDescription == nil || *out[0].ErrorDescription != desc {
+		t.Fatalf("error_description: got %v, want %q (equal-severity ECC finding must not clobber it)", out[0].ErrorDescription, desc)
+	}
+}
+
+func TestEnrichPCIeWithNVIDIAData_resetRequiredEscalatesOverExistingWarning(t *testing.T) {
+	vendorID := NvidiaVendorID
+	bdf := "0000:65:00.0"
+	status := statusWarning
+	desc := "PCIe link speed degraded: running at Gen1, capable of Gen4"
+	devices := []schema.HardwarePCIeDevice{
+		{
+			HardwareComponentStatus: schema.HardwareComponentStatus{Status: &status, ErrorDescription: &desc},
+			VendorID:                &vendorID,
+			BDF:                     &bdf,
+		},
+	}
+
+	byBDF := map[string]nvidiaGPUInfo{
+		"0000:65:00.0": {ResetRequired: ptrBool(true)},
+	}
+
+	out := enrichPCIeWithNVIDIAData(devices, byBDF, true)
+	if out[0].Status == nil || *out[0].Status != statusCritical {
+		t.Fatalf("status: got %v, want %v (reset-required Critical must escalate over the PCIe-link Warning)", out[0].Status, statusCritical)
+	}
+	if out[0].ErrorDescription == nil || *out[0].ErrorDescription != "GPU requires a reset" {
+		t.Fatalf("error_description: got %v", out[0].ErrorDescription)
+	}
+}
+
+func TestEnrichPCIeWithNVIDIAData_regressionNoOverride(t *testing.T) {
+	vendorID := NvidiaVendorID
+	bdf := "0000:65:00.0"
+	devices := []schema.HardwarePCIeDevice{
+		{VendorID: &vendorID, BDF: &bdf},
+	}
+
+	byBDF := map[string]nvidiaGPUInfo{
+		"0000:65:00.0": {},
+	}
+
+	out := enrichPCIeWithNVIDIAData(devices, byBDF, true)
+	if out[0].Status == nil || *out[0].Status != statusOK {
+		t.Fatalf("status: got %v, want %v", out[0].Status, statusOK)
+	}
+	if out[0].ErrorDescription != nil {
+		t.Fatalf("error_description: got %v, want nil", out[0].ErrorDescription)
+	}
+}
+
 func ptrInt64(v int64) *int64     { return &v }
 func ptrFloat(v float64) *float64 { return &v }
 func ptrBool(v bool) *bool        { return &v }