diff --git a/cmd/buildkitd/config/gcpolicy.go b/cmd/buildkitd/config/gcpolicy.go
index 021d8b5d5..62cd824f0 100644
--- a/cmd/buildkitd/config/gcpolicy.go
+++ b/cmd/buildkitd/config/gcpolicy.go
@@ -78,7 +78,7 @@ func DefaultGCPolicy(cfg GCConfig, dstat disk.DiskStat) []GCPolicy {
 	return []GCPolicy{
 		// if build cache uses more than 512MB delete the most easily reproducible data after it has not been used for 2 days
 		{
-			Filters:      []string{"type==source.local,type==exec.cachemount,type==source.git.checkout"},
+			Filters:      []string{"type==source.local", "type==exec.cachemount", "type==source.git.checkout"},
 			KeepDuration: Duration{Duration: time.Duration(48) * time.Hour}, // 48h
 			MaxUsedSpace: DiskSpace{Bytes: 512 * 1e6},                       // 512MB
 		},
diff --git a/cmd/buildkitd/config/gcpolicy_test.go b/cmd/buildkitd/config/gcpolicy_test.go
new file mode 100644
index 000000000..0cd4409ef
--- /dev/null
+++ b/cmd/buildkitd/config/gcpolicy_test.go
@@ -0,0 +1,43 @@
+package config
+
+import (
+	"testing"
+
+	"github.com/containerd/containerd/v2/pkg/filters"
+	"github.com/moby/buildkit/client"
+	"github.com/moby/buildkit/util/disk"
+	"github.com/stretchr/testify/require"
+)
+
+func TestDefaultGCPolicyFiltersMatch(t *testing.T) {
+	policies := DefaultGCPolicy(GCConfig{}, disk.DiskStat{Total: 1e12})
+	require.NotEmpty(t, policies)
+
+	rule := policies[0]
+	require.NotEmpty(t, rule.Filters)
+
+	f, err := filters.ParseAll(rule.Filters...)
+	require.NoError(t, err)
+
+	adapt := func(rt client.UsageRecordType) filters.Adaptor {
+		return filters.AdapterFunc(func(fieldpath []string) (string, bool) {
+			if len(fieldpath) == 1 && fieldpath[0] == "type" {
+				return string(rt), rt != ""
+			}
+			return "", false
+		})
+	}
+
+	for _, rt := range []client.UsageRecordType{
+		client.UsageRecordTypeLocalSource,
+		client.UsageRecordTypeCacheMount,
+		client.UsageRecordTypeGitCheckout,
+	} {
+		require.Truef(t, f.Match(adapt(rt)),
+			"first default GC policy should match record type %q", rt)
+	}
+
+	// It must not match unrelated records such as regular build cache.
+	require.Falsef(t, f.Match(adapt(client.UsageRecordTypeRegular)),
+		"first default GC policy should not match record type %q", client.UsageRecordTypeRegular)
+}