3.5.7.2 -stable review patch. If anyone has any objections, please let me know.
------------------ From: "jeff.liu" <[email protected]> commit 5175a5e76bbdf20a614fb47ce7a38f0f39e70226 upstream. This is the revised patch for fixing rds-ping spinlock recursion according to Venkat's suggestions. RDS ping/pong over TCP feature has been broken for years(2.6.39 to 3.6.0) since we have to set TCP cork and call kernel_sendmsg() between ping/pong which both need to lock "struct sock *sk". However, this lock has already been hold before rds_tcp_data_ready() callback is triggerred. As a result, we always facing spinlock resursion which would resulting in system panic. Given that RDS ping is only used to test the connectivity and not for serious performance measurements, we can queue the pong transmit to rds_wq as a delayed response. Reported-by: Dan Carpenter <[email protected]> CC: Venkat Venkatsubra <[email protected]> CC: David S. Miller <[email protected]> CC: James Morris <[email protected]> Signed-off-by: Jie Liu <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Herton Ronaldo Krzesinski <[email protected]> --- net/rds/send.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/rds/send.c b/net/rds/send.c index 96531d4..88eace5 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -1122,7 +1122,7 @@ rds_send_pong(struct rds_connection *conn, __be16 dport) rds_stats_inc(s_send_pong); if (!test_bit(RDS_LL_SEND_FULL, &conn->c_flags)) - rds_send_xmit(conn); + queue_delayed_work(rds_wq, &conn->c_send_w, 0); rds_message_put(rm); return 0; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
