From a5c57d327272bdf3a8b19686eaca2ec683449e67 Mon Sep 17 00:00:00 2001 From: Parav Pandit Date: Mon, 14 May 2018 11:11:07 +0300 Subject: [PATCH] IB/cm: Avoid AV ah_attr overwriting during LAP message handling AH attribute of the cm_id can be overwritten if LAP message is received on CM request which is in progress. This bug got introduced to avoid sleeping when spin lock is held as part of commit in Fixes tag. Therefore validate the cm_id state first and continue to perform AV ah_attr initialization. Given that Aleternative path related messages are not supported for RoCE, init_av_from_response/path is such messages are ok to be called from blocking context. Fixes: 33f93e1ebcf5 ("IB/cm: Fix sleeping while spin lock is held") Signed-off-by: Parav Pandit Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe --- drivers/infiniband/core/cm.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c index a92e1a5..34b4def 100644 --- a/drivers/infiniband/core/cm.c +++ b/drivers/infiniband/core/cm.c @@ -3189,12 +3189,6 @@ static int cm_lap_handler(struct cm_work *work) if (!cm_id_priv) return -EINVAL; - ret = cm_init_av_for_response(work->port, work->mad_recv_wc->wc, - work->mad_recv_wc->recv_buf.grh, - &cm_id_priv->av); - if (ret) - goto deref; - param = &work->cm_event.param.lap_rcvd; memset(&work->path[0], 0, sizeof(work->path[1])); cm_path_set_rec_type(work->port->cm_dev->ib_device, @@ -3239,10 +3233,16 @@ static int cm_lap_handler(struct cm_work *work) goto unlock; } - cm_id_priv->id.lap_state = IB_CM_LAP_RCVD; - cm_id_priv->tid = lap_msg->hdr.tid; + ret = cm_init_av_for_response(work->port, work->mad_recv_wc->wc, + work->mad_recv_wc->recv_buf.grh, + &cm_id_priv->av); + if (ret) + goto unlock; + cm_init_av_by_path(param->alternate_path, &cm_id_priv->alt_av, cm_id_priv); + cm_id_priv->id.lap_state = IB_CM_LAP_RCVD; + cm_id_priv->tid = lap_msg->hdr.tid; ret = atomic_inc_and_test(&cm_id_priv->work_count); if (!ret) list_add_tail(&work->list, &cm_id_priv->work_list); -- 2.7.4