IB/hfi1: Add additional checks when handling TID RDMA WRITE DATA packet

In a congested fabric with adaptive routing enabled, traces show that
packets could be delivered out of order, which could cause incorrect
processing of stale packets. For stale TID RDMA WRITE DATA packets that
cause KDETH EFLAGS errors, this patch adds additional checks before
processing the packets.

Fixes: d72fe7d5008b ("IB/hfi1: Add a function to receive TID RDMA WRITE DATA packet")
Cc: <stable@vger.kernel.org>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Link: https://lore.kernel.org/r/20190815192051.105923.69979.stgit@awfm-01.aw.intel.com
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/infiniband/hw/hfi1/tid_rdma.c b/drivers/infiniband/hw/hfi1/tid_rdma.c
index 23bb2498e5b479394014d9eac3e210825ad4956e..7bccb59d8a30991db6a1d3a0a3b5c4454cde73c7 100644 (file)
--- a/drivers/infiniband/hw/hfi1/tid_rdma.c
+++ b/drivers/infiniband/hw/hfi1/tid_rdma.c
@@ -2945,8 +2945,15 @@ bool hfi1_handle_kdeth_eflags(struct hfi1_ctxtdata *rcd,
         */
        spin_lock(&qp->s_lock);
        qpriv = qp->priv;
+       if (qpriv->r_tid_tail == HFI1_QP_WQE_INVALID ||
+           qpriv->r_tid_tail == qpriv->r_tid_head)
+               goto unlock;
        e = &qp->s_ack_queue[qpriv->r_tid_tail];
+       if (e->opcode != TID_OP(WRITE_REQ))
+               goto unlock;
        req = ack_to_tid_req(e);
+       if (req->comp_seg == req->cur_seg)
+               goto unlock;
        flow = &req->flows[req->clear_tail];
        trace_hfi1_eflags_err_write(qp, rcv_type, rte, psn);
        trace_hfi1_rsp_handle_kdeth_eflags(qp, psn);