On Fri, 15 Aug 2025 15:02:06 +1000 alistair23@gmail.com wrote:

As part of supporting KeyUpdate we are going to pass errors up to the
callers of TLS to indaicate a KeyUpdate. Those layers will need to handle
the KeyUpdate and as part of that clear the error.

+static inline void tls_clear_err(struct sock *sk)
+{
+	WRITE_ONCE(sk->sk_err, 0);
+	/* Paired with smp_rmb() in tcp_poll() */
+	smp_wmb();

Please explain how the key error ends up recorded on the socket.