From c058ecf6e455fac7346d46197a02398ead90851f Mon Sep 17 00:00:00 2001 From: Steve Wise Date: Mon, 27 Nov 2017 13:16:32 -0800 Subject: [PATCH] iw_cxgb4: only insert drain cqes if wq is flushed Only insert our special drain CQEs to support ib_drain_sq/rq() after the wq is flushed. Otherwise, existing but not yet polled CQEs can be returned out of order to the user application. This can happen when the QP has exited RTS but not yet flushed the QP, which can happen during a normal close (vs abortive close). In addition never count the drain CQEs when determining how many CQEs need to be synthesized during the flush operation. This latter issue should never happen if the QP is properly flushed before inserting the drain CQE, but I wanted to avoid corrupting the CQ state. So we handle it and log a warning once. Fixes: 4fe7c2962e11 ("iw_cxgb4: refactor sq/rq drain logic") Signed-off-by: Steve Wise Cc: stable@vger.kernel.org Signed-off-by: Jason Gunthorpe --- drivers/infiniband/hw/cxgb4/cq.c | 5 +++++ drivers/infiniband/hw/cxgb4/qp.c | 14 ++++++++++++-- 2 files changed, 17 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/hw/cxgb4/cq.c b/drivers/infiniband/hw/cxgb4/cq.c index ea55e95cd2c5..b7bfc536e00f 100644 --- a/drivers/infiniband/hw/cxgb4/cq.c +++ b/drivers/infiniband/hw/cxgb4/cq.c @@ -395,6 +395,11 @@ void c4iw_flush_hw_cq(struct c4iw_cq *chp) static int cqe_completes_wr(struct t4_cqe *cqe, struct t4_wq *wq) { + if (CQE_OPCODE(cqe) == C4IW_DRAIN_OPCODE) { + WARN_ONCE(1, "Unexpected DRAIN CQE qp id %u!\n", wq->sq.qid); + return 0; + } + if (CQE_OPCODE(cqe) == FW_RI_TERMINATE) return 0; diff --git a/drivers/infiniband/hw/cxgb4/qp.c b/drivers/infiniband/hw/cxgb4/qp.c index 355e288ec969..38bddd02a943 100644 --- a/drivers/infiniband/hw/cxgb4/qp.c +++ b/drivers/infiniband/hw/cxgb4/qp.c @@ -868,7 +868,12 @@ int c4iw_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr, qhp = to_c4iw_qp(ibqp); spin_lock_irqsave(&qhp->lock, flag); - if (t4_wq_in_error(&qhp->wq)) { + + /* + * If the qp has been flushed, then just insert a special + * drain cqe. + */ + if (qhp->wq.flushed) { spin_unlock_irqrestore(&qhp->lock, flag); complete_sq_drain_wr(qhp, wr); return err; @@ -1011,7 +1016,12 @@ int c4iw_post_receive(struct ib_qp *ibqp, struct ib_recv_wr *wr, qhp = to_c4iw_qp(ibqp); spin_lock_irqsave(&qhp->lock, flag); - if (t4_wq_in_error(&qhp->wq)) { + + /* + * If the qp has been flushed, then just insert a special + * drain cqe. + */ + if (qhp->wq.flushed) { spin_unlock_irqrestore(&qhp->lock, flag); complete_rq_drain_wr(qhp, wr); return err; -- GitLab