1 files changed, 1 insertions, 1 deletions

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 38a7427ae902..be6223c586fa 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -924,7 +924,7 @@ struct tcp_congestion_ops {
         void (*cwnd_event)(struct sock *sk, enum tcp_ca_event ev);
         /* call when ack arrives (optional) */
         void (*in_ack_event)(struct sock *sk, u32 flags);
-        /* new value of cwnd after loss (optional) */
+        /* new value of cwnd after loss (required) */
         u32  (*undo_cwnd)(struct sock *sk);
         /* hook for packet ack accounting (optional) */
         void (*pkts_acked)(struct sock *sk, const struct ack_sample *sample);