From 97c45c2c28cd291e06778d9d36a0f60ee74726bc Mon Sep 17 00:00:00 2001 From: Parav Pandit Date: Sun, 25 Mar 2018 13:40:19 +0300 Subject: [PATCH] IB/cm: Block processing alternate path handling RoCE Rx cm messages Due to below reasons, it is better to not support alternate path receive messages for RoCE in near term. 1. Alternate path for RoCE is not supported at rdmacm layer. 2. It is not supported in uverbs/core layer for RoCE. 3. Alternate path for IPv6 for link local address cannot resolve route determinstically without a valid incoming interface id whose usecase make sense only with dual port mode. 4. init_av_from_path while processing LAP messages for IB and RoCE can lead to adding duplicate entry of AV into the port list, leads to list corruption. 5. rdma-core userspace a well known userspace implementation has removed support of libucm which use ucm.ko module, which is the only module that can trigger alternate path related messages. 6. ucm kernel module is requested to be removed from the IB core in patch [1]. [1] https://patchwork.kernel.org/patch/10268503/ Signed-off-by: Parav Pandit Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe --- drivers/infiniband/core/cm.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c index 38d79bc1bf78..a92e1a5c202b 100644 --- a/drivers/infiniband/core/cm.c +++ b/drivers/infiniband/core/cm.c @@ -3175,6 +3175,13 @@ static int cm_lap_handler(struct cm_work *work) struct ib_mad_send_buf *msg = NULL; int ret; + /* Currently Alternate path messages are not supported for + * RoCE link layer. + */ + if (rdma_protocol_roce(work->port->cm_dev->ib_device, + work->port->port_num)) + return -EINVAL; + /* todo: verify LAP request and send reject APR if invalid. */ lap_msg = (struct cm_lap_msg *)work->mad_recv_wc->recv_buf.mad; cm_id_priv = cm_acquire_id(lap_msg->remote_comm_id, @@ -3324,6 +3331,13 @@ static int cm_apr_handler(struct cm_work *work) struct cm_apr_msg *apr_msg; int ret; + /* Currently Alternate path messages are not supported for + * RoCE link layer. + */ + if (rdma_protocol_roce(work->port->cm_dev->ib_device, + work->port->port_num)) + return -EINVAL; + apr_msg = (struct cm_apr_msg *)work->mad_recv_wc->recv_buf.mad; cm_id_priv = cm_acquire_id(apr_msg->remote_comm_id, apr_msg->local_comm_id);