From af295892a7abbf05a3c2ba7abc4d81bb448623d6 Mon Sep 17 00:00:00 2001 From: Petr Malat Date: Fri, 16 May 2025 10:17:28 +0200 Subject: [PATCH] sctp: Do not wake readers in __sctp_write_space() Function __sctp_write_space() doesn't set poll key, which leads to ep_poll_callback() waking up all waiters, not only these waiting for the socket being writable. Set the key properly using wake_up_interruptible_poll(), which is preferred over the sync variant, as writers are not woken up before at least half of the queue is available. Also, TCP does the same. Signed-off-by: Petr Malat Acked-by: Xin Long Link: https://patch.msgid.link/20250516081727.1361451-1-oss@malat.biz Signed-off-by: Jakub Kicinski --- net/sctp/socket.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 85a9dfeff4d6..90b75d4ec329 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -9100,7 +9100,8 @@ static void __sctp_write_space(struct sctp_association *asoc) wq = rcu_dereference(sk->sk_wq); if (wq) { if (waitqueue_active(&wq->wait)) - wake_up_interruptible(&wq->wait); + wake_up_interruptible_poll(&wq->wait, EPOLLOUT | + EPOLLWRNORM | EPOLLWRBAND); /* Note that we try to include the Async I/O support * here by modeling from the current TCP/UDP code. -- 2.25.1