Re: [PATCH net-next net] netdev: Hide the netdev_priv() origin from GCC in netdev_from_priv()

--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h

@@ -2838,6 +2838,13 @@ static inline void *netdev_priv(const struct net_device *dev)
   */
  static inline struct net_device *netdev_from_priv(const void *priv)
  {
+	/*
+	 * When GCC can see that @priv came from netdev_priv(), it can
+	 * compute an object size of 0 for the net_device and its members,
+	 * which makes FORTIFY_SOURCE fail valid accesses through the result:
+	 * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127875
+	 */
+	OPTIMIZER_HIDE_VAR(priv);