Commit 9de0864c authored by Andy Grover's avatar Andy Grover
Browse files

RDS: Fix locking in send on m_rs_lock 



Do not nest m_rs_lock under c_lock

Disable interrupts in {rdma,atomic}_send_complete

Signed-off-by: default avatarAndy Grover <andy.grover@oracle.com>
parent 7c82eaf0

net/rds/send.c

+8 −7
Original line number Diff line number Diff line
@@ -415,8 +415,9 @@ void rds_rdma_send_complete(struct rds_message *rm, int status) 
	struct rds_sock *rs = NULL;

	struct rds_rdma_op *ro;

	struct rds_notifier *notifier;

	unsigned long flags;



	spin_lock(&rm->m_rs_lock);

	spin_lock_irqsave(&rm->m_rs_lock, flags);



	ro = rm->m_rdma_op;

	if (test_bit(RDS_MSG_ON_SOCK, &rm->m_flags) &&
@@ -433,7 +434,7 @@ void rds_rdma_send_complete(struct rds_message *rm, int status) 
		ro->r_notifier = NULL;

	}



	spin_unlock(&rm->m_rs_lock);

	spin_unlock_irqrestore(&rm->m_rs_lock, flags);



	if (rs) {

		rds_wake_sk_sleep(rs);
@@ -647,8 +648,8 @@ void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in *dest) 
	list_for_each_entry(rm, &list, m_sock_item) {



		conn = rm->m_inc.i_conn;

		spin_lock_irqsave(&conn->c_lock, flags);



		spin_lock_irqsave(&conn->c_lock, flags);

		/*

		 * Maybe someone else beat us to removing rm from the conn.

		 * If we race with their flag update we'll get the lock and
@@ -658,23 +659,23 @@ void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in *dest) 
			spin_unlock_irqrestore(&conn->c_lock, flags);

			continue;

		}

		list_del_init(&rm->m_conn_item);

		spin_unlock_irqrestore(&conn->c_lock, flags);



		/*

		 * Couldn't grab m_rs_lock in top loop (lock ordering),

		 * but we can now.

		 */

		spin_lock(&rm->m_rs_lock);

		spin_lock_irqsave(&rm->m_rs_lock, flags);



		spin_lock(&rs->rs_lock);

		__rds_rdma_send_complete(rs, rm, RDS_RDMA_CANCELED);

		spin_unlock(&rs->rs_lock);



		rm->m_rs = NULL;

		spin_unlock(&rm->m_rs_lock);

		spin_unlock_irqrestore(&rm->m_rs_lock, flags);



		list_del_init(&rm->m_conn_item);

		rds_message_put(rm);

		spin_unlock_irqrestore(&conn->c_lock, flags);

	}



	rds_wake_sk_sleep(rs);