From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Ka-Cheong Poon , "David S . Miller" , Sasha Levin Subject: [PATCH AUTOSEL 4.18 21/27] rds: RDS (tcp) hangs on sendto() to unresponding address Date: Mon, 22 Oct 2018 06:19:18 -0400 Message-Id: <20181022101924.40531-21-sashal@kernel.org> In-Reply-To: <20181022101924.40531-1-sashal@kernel.org> References: <20181022101924.40531-1-sashal@kernel.org> List-ID: From: Ka-Cheong Poon [ Upstream commit 9a4890bd6d6325a1c88564a20ab310b2d56f6094 ] In rds_send_mprds_hash(), if the calculated hash value is non-zero and the MPRDS connections are not yet up, it will wait. But it should not wait if the send is non-blocking. In this case, it should just use the base c_path for sending the message. Signed-off-by: Ka-Cheong Poon Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/rds/send.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/net/rds/send.c b/net/rds/send.c index 59f17a2335f4..0e54ca0f4e9e 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -1006,7 +1006,8 @@ static int rds_cmsg_send(struct rds_sock *rs, struct rds_message *rm, return ret; } -static int rds_send_mprds_hash(struct rds_sock *rs, struct rds_connection *conn) +static int rds_send_mprds_hash(struct rds_sock *rs, + struct rds_connection *conn, int nonblock) { int hash; @@ -1022,10 +1023,16 @@ static int rds_send_mprds_hash(struct rds_sock *rs, struct rds_connection *conn) * used. But if we are interrupted, we have to use the zero * c_path in case the connection ends up being non-MP capable. */ - if (conn->c_npaths == 0) + if (conn->c_npaths == 0) { + /* Cannot wait for the connection be made, so just use + * the base c_path. + */ + if (nonblock) + return 0; if (wait_event_interruptible(conn->c_hs_waitq, conn->c_npaths != 0)) hash = 0; + } if (conn->c_npaths == 1) hash = 0; } @@ -1170,7 +1177,7 @@ int rds_sendmsg(struct socket *sock, struct msghdr *msg, size_t payload_len) } if (conn->c_trans->t_mp_capable) - cpath = &conn->c_path[rds_send_mprds_hash(rs, conn)]; + cpath = &conn->c_path[rds_send_mprds_hash(rs, conn, nonblock)]; else cpath = &conn->c_path[0]; -- 2.17.1