From: Ying Xue <ying.xue@xxxxxxxxxxxxx> Currently connection shutdown callback function is called when connection instance is released in tipc_conn_kref_release(), and receiving packets and sending packets are running in different threads. Even if connection is closed by the thread of receiving packets, its shutdown callback may not be called immediately as the connection reference count is non-zero at that moment. So, although the connection is shut down by the thread of receiving packets, the thread of sending packets doesn't know it. Before its shutdown callback is invoked to tell the sending thread its connection has been closed, the sending thread may deliver messages by tipc_conn_sendmsg(), this is why the following error information appears: "Sending subscription event failed, no memory" To eliminate it, allow connection shutdown callback function to be called before connection id is removed in tipc_close_conn(), which makes the sending thread know the truth in time that its socket is closed so that it doesn't send message to it. Signed-off-by: Ying Xue <ying.xue@xxxxxxxxxxxxx> Acked-by: Erik Hugne <erik.hugne@xxxxxxxxxxxx> Reviewed-by: Jon Maloy <jon.maloy@xxxxxxxxxxxx> --- net/tipc/config.c | 2 +- net/tipc/server.c | 8 +++----- net/tipc/subscr.c | 2 +- 3 files changed, 5 insertions(+), 7 deletions(-) diff --git a/net/tipc/config.c b/net/tipc/config.c index c301a9a..7dd2dd1 100644 --- a/net/tipc/config.c +++ b/net/tipc/config.c @@ -401,7 +401,7 @@ static void cfg_conn_msg_event(int conid, struct sockaddr_tipc *addr, ret = tipc_conn_sendmsg(&cfgsrv, conid, addr, rep_buf->data, rep_buf->len); - if (ret < 0) + if (ret == -ENOMEM) pr_err("Sending cfg reply message failed, no memory\n"); kfree_skb(rep_buf); diff --git a/net/tipc/server.c b/net/tipc/server.c index b635ca3..cee66cf 100644 --- a/net/tipc/server.c +++ b/net/tipc/server.c @@ -87,7 +87,6 @@ static void tipc_clean_outqueues(struct tipc_conn *con); static void tipc_conn_kref_release(struct kref *kref) { struct tipc_conn *con = container_of(kref, struct tipc_conn, kref); - struct tipc_server *s = con->server; if (con->sock) { tipc_sock_release_local(con->sock); @@ -95,10 +94,6 @@ static void tipc_conn_kref_release(struct kref *kref) } tipc_clean_outqueues(con); - - if (con->conid) - s->tipc_conn_shutdown(con->conid, con->usr_data); - kfree(con); } @@ -181,6 +176,9 @@ static void tipc_close_conn(struct tipc_conn *con) struct tipc_server *s = con->server; if (test_and_clear_bit(CF_CONNECTED, &con->flags)) { + if (con->conid) + s->tipc_conn_shutdown(con->conid, con->usr_data); + spin_lock_bh(&s->idr_lock); idr_remove(&s->conn_idr, con->conid); s->idr_in_use--; diff --git a/net/tipc/subscr.c b/net/tipc/subscr.c index 7cb0bd5..a6a6a26 100644 --- a/net/tipc/subscr.c +++ b/net/tipc/subscr.c @@ -108,7 +108,7 @@ static void subscr_send_event(struct tipc_subscription *sub, u32 found_lower, sub->evt.port.node = htohl(node, sub->swap); ret = tipc_conn_sendmsg(&topsrv, subscriber->conid, NULL, msg_sect.iov_base, msg_sect.iov_len); - if (ret < 0) + if (ret == -ENOMEM) pr_err("Sending subscription event failed, no memory\n"); } -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html