From c9e65383a20d9a656db70efbf67e57f8115ad776 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Tue, 11 May 2010 15:14:16 -0700 Subject: [PATCH] rds: Fix RDMA message reference counting The RDS send_xmit code was trying to get fancy with message counting and was dropping the final reference on the RDMA messages too early. This resulted in memory corruption and oopsen. The fix here is to always add a ref as the parts of the message passes through rds_send_xmit, and always drop a ref as the parts of the message go through completion handling. Signed-off-by: Chris Mason --- net/rds/ib_send.c | 11 ++++++----- net/rds/send.c | 11 ++++++++--- 2 files changed, 14 insertions(+), 8 deletions(-) diff --git a/net/rds/ib_send.c b/net/rds/ib_send.c index 657037d96cbf..82459e52c771 100644 --- a/net/rds/ib_send.c +++ b/net/rds/ib_send.c @@ -268,11 +268,12 @@ void rds_ib_send_cq_comp_handler(struct ib_cq *cq, void *context) if (send->s_queued + HZ/2 < jiffies) rds_ib_stats_inc(s_ib_tx_stalled); - if (&send->s_op == &rm->m_final_op) { - /* If anyone waited for this message to get flushed out, wake - * them up now */ - rds_message_unmapped(rm); - + if (send->s_op) { + if (send->s_op == rm->m_final_op) { + /* If anyone waited for this message to get flushed out, wake + * them up now */ + rds_message_unmapped(rm); + } rds_message_put(rm); send->s_op = NULL; } diff --git a/net/rds/send.c b/net/rds/send.c index d35c43ff792e..5c6d4a0be0d7 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -68,7 +68,6 @@ void rds_send_reset(struct rds_connection *conn) * transport. This isn't entirely true (it's flushed out * independently) but as the connection is down, there's * no ongoing RDMA to/from that memory */ -printk(KERN_CRIT "send reset unmapping %p\n", rm); rds_message_unmapped(rm); spin_unlock_irqrestore(&conn->c_send_lock, flags); @@ -234,10 +233,13 @@ int rds_send_xmit(struct rds_connection *conn) /* The transport either sends the whole rdma or none of it */ if (rm->rdma.op_active && !conn->c_xmit_rdma_sent) { + rds_message_addref(rm); rm->m_final_op = &rm->rdma; ret = conn->c_trans->xmit_rdma(conn, &rm->rdma); - if (ret) + if (ret) { + rds_message_put(rm); break; + } conn->c_xmit_rdma_sent = 1; /* The transport owns the mapped memory for now. @@ -246,10 +248,13 @@ int rds_send_xmit(struct rds_connection *conn) } if (rm->atomic.op_active && !conn->c_xmit_atomic_sent) { + rds_message_addref(rm); rm->m_final_op = &rm->atomic; ret = conn->c_trans->xmit_atomic(conn, &rm->atomic); - if (ret) + if (ret) { + rds_message_put(rm); break; + } conn->c_xmit_atomic_sent = 1; /* The transport owns the mapped memory for now. -- GitLab