Merge tag 'v5.16-rc5' into locking/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 9 insertions, 23 deletions

diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index 7c3420afb1a0..fe98e4f475ba 100644
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -422,28 +422,6 @@ bool mptcp_syn_options(struct sock *sk, const struct sk_buff *skb,
 	return false;
 }
 
-/* MP_JOIN client subflow must wait for 4th ack before sending any data:
- * TCP can't schedule delack timer before the subflow is fully established.
- * MPTCP uses the delack timer to do 3rd ack retransmissions
- */
-static void schedule_3rdack_retransmission(struct sock *sk)
-{
-	struct inet_connection_sock *icsk = inet_csk(sk);
-	struct tcp_sock *tp = tcp_sk(sk);
-	unsigned long timeout;
-
-	/* reschedule with a timeout above RTT, as we must look only for drop */
-	if (tp->srtt_us)
-		timeout = tp->srtt_us << 1;
-	else
-		timeout = TCP_TIMEOUT_INIT;
-
-	WARN_ON_ONCE(icsk->icsk_ack.pending & ICSK_ACK_TIMER);
-	icsk->icsk_ack.pending |= ICSK_ACK_SCHED | ICSK_ACK_TIMER;
-	icsk->icsk_ack.timeout = timeout;
-	sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout);
-}
-
 static void clear_3rdack_retransmission(struct sock *sk)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
@@ -526,7 +504,15 @@ static bool mptcp_established_options_mp(struct sock *sk, struct sk_buff *skb,
 		*size = TCPOLEN_MPTCP_MPJ_ACK;
 		pr_debug("subflow=%p", subflow);
 
-		schedule_3rdack_retransmission(sk);
+		/* we can use the full delegate action helper only from BH context
+		 * If we are in process context - sk is flushing the backlog at
+		 * socket lock release time - just set the appropriate flag, will
+		 * be handled by the release callback
+		 */
+		if (sock_owned_by_user(sk))
+			set_bit(MPTCP_DELEGATE_ACK, &subflow->delegated_status);
+		else
+			mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_ACK);
 		return true;
 	}
 	return false;