diff --git a/src/include/device/device.h b/src/include/device/device.h
index b2221cc..f24e4b2 100644
--- a/src/include/device/device.h
+++ b/src/include/device/device.h
@@ -298,7 +298,14 @@
 DEVTREE_CONST struct device *pcidev_on_root(uint8_t dev, uint8_t fn);
 DEVTREE_CONST struct bus *pci_root_bus(void);
 
-/* To be deprecated, avoid using. */
+/* To be deprecated, avoid using.
+ *
+ * Note that this function can return the incorrect device prior
+ * to PCI enumeration because the secondary field of the bus object
+ * is 0. The failing scenario is determined by the order of the
+ * devices in all_devices singly-linked list as well as the time
+ * when this function is called (secondary reflecting topology).
+ */
 DEVTREE_CONST struct device *dev_find_slot(unsigned int bus, unsigned int devfn);
 DEVTREE_CONST struct device *pcidev_path_on_root_debug(pci_devfn_t devfn, const char *func);