RDS: Fix send locking issue

Fix a deadlock between rds_rdma_send_complete() and
rds_send_remove_from_sock() when rds socket lock and
rds message lock are acquired out-of-order.

Signed-off-by: Tina Yang <Tina.Yang@oracle.com>
Signed-off-by: Andy Grover <andy.grover@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tina Yang 2010-03-11 13:50:00 +00:00 committed by David S. Miller
parent 2e7b3b9945
commit 048c15e641

View File

@ -533,14 +533,13 @@ void rds_send_remove_from_sock(struct list_head *messages, int status)
if (rs != rm->m_rs) {
if (rs) {
spin_unlock(&rs->rs_lock);
rds_wake_sk_sleep(rs);
sock_put(rds_rs_to_sk(rs));
}
rs = rm->m_rs;
spin_lock(&rs->rs_lock);
sock_hold(rds_rs_to_sk(rs));
}
spin_lock(&rs->rs_lock);
if (test_and_clear_bit(RDS_MSG_ON_SOCK, &rm->m_flags)) {
struct rds_rdma_op *ro = rm->m_rdma_op;
@ -560,6 +559,7 @@ void rds_send_remove_from_sock(struct list_head *messages, int status)
rds_message_put(rm);
rm->m_rs = NULL;
}
spin_unlock(&rs->rs_lock);
unlock_and_drop:
spin_unlock(&rm->m_rs_lock);
@ -567,7 +567,6 @@ unlock_and_drop:
}
if (rs) {
spin_unlock(&rs->rs_lock);
rds_wake_sk_sleep(rs);
sock_put(rds_rs_to_sk(rs));
}