diff --git a/sys/dev/acpica/acpi.c b/sys/dev/acpica/acpi.c
--- a/sys/dev/acpica/acpi.c
+++ b/sys/dev/acpica/acpi.c
@@ -1629,7 +1629,8 @@
 	    " (type=%d, rid=%d)\n", type, rid);
 	return;
     }
-    resource_list_unreserve(rl, bus, child, type, rid);
+    if (resource_list_reserved(rl, type, rid))
+	resource_list_unreserve(rl, bus, child, type, rid);
     resource_list_delete(rl, type, rid);
 }