diff options
Diffstat (limited to 'net/rds/tcp.c')
| -rw-r--r-- | net/rds/tcp.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/net/rds/tcp.c b/net/rds/tcp.c index 7ab1b41ffc88..74ee126a6fe6 100644 --- a/net/rds/tcp.c +++ b/net/rds/tcp.c @@ -148,11 +148,23 @@ void rds_tcp_reset_callbacks(struct socket *sock, * potentially have transitioned to the RDS_CONN_UP state, * so we must quiesce any send threads before resetting * c_transport_data. We quiesce these threads by setting - * cp_state to something other than RDS_CONN_UP, and then + * c_state to something other than RDS_CONN_UP, and then * waiting for any existing threads in rds_send_xmit to * complete release_in_xmit(). (Subsequent threads entering * rds_send_xmit() will bail on !rds_conn_up(). + * + * However an incoming syn-ack at this point would end up + * marking the conn as RDS_CONN_UP, and would again permit + * rds_send_xmi() threads through, so ideally we would + * synchronize on RDS_CONN_UP after lock_sock(), but cannot + * do that: waiting on !RDS_IN_XMIT after lock_sock() may + * end up deadlocking with tcp_sendmsg(), and the RDS_IN_XMIT + * would not get set. As a result, we set c_state to + * RDS_CONN_RESETTTING, to ensure that rds_tcp_state_change + * cannot mark rds_conn_path_up() in the window before lock_sock() */ + atomic_set(&conn->c_state, RDS_CONN_RESETTING); + wait_event(conn->c_waitq, !test_bit(RDS_IN_XMIT, &conn->c_flags)); lock_sock(osock->sk); /* reset receive side state for rds_tcp_data_recv() for osock */ if (tc->t_tinc) { |