The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From d14587334580bc94d3ee11e8320e0c157f91ae8f Mon Sep 17 00:00:00 2001

From: Steve Wise swise@opengridcomputing.com Date: Tue, 19 Dec 2017 14:02:10 -0800 Subject: [PATCH] iw_cxgb4: when flushing, complete all wrs in a chain

If a wr chain was posted and needed to be flushed, only the first wr in the chain was completed with FLUSHED status. The rest were never completed. This caused isert to hang on shutdown due to the missing completions which left iscsi IO commands referenced, stalling the shutdown.

Fixes: 4fe7c2962e11 ("iw_cxgb4: refactor sq/rq drain logic")

Cc: stable@vger.kernel.org Signed-off-by: Steve Wise swise@opengridcomputing.com Signed-off-by: Jason Gunthorpe jgg@mellanox.com

diff --git a/drivers/infiniband/hw/cxgb4/qp.c b/drivers/infiniband/hw/cxgb4/qp.c index 21495f917bcc..d5c92fc520d6 100644 --- a/drivers/infiniband/hw/cxgb4/qp.c +++ b/drivers/infiniband/hw/cxgb4/qp.c @@ -858,6 +858,22 @@ static int complete_sq_drain_wr(struct c4iw_qp *qhp, struct ib_send_wr *wr) return 0; }

+static int complete_sq_drain_wrs(struct c4iw_qp *qhp, struct ib_send_wr *wr, + struct ib_send_wr **bad_wr) +{ + int ret = 0; + + while (wr) { + ret = complete_sq_drain_wr(qhp, wr); + if (ret) { + *bad_wr = wr; + break; + } + wr = wr->next; + } + return ret; +} + static void complete_rq_drain_wr(struct c4iw_qp *qhp, struct ib_recv_wr *wr) { struct t4_cqe cqe = {}; @@ -890,6 +906,14 @@ static void complete_rq_drain_wr(struct c4iw_qp *qhp, struct ib_recv_wr *wr) } }

+static void complete_rq_drain_wrs(struct c4iw_qp *qhp, struct ib_recv_wr *wr) +{ + while (wr) { + complete_rq_drain_wr(qhp, wr); + wr = wr->next; + } +} + int c4iw_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr, struct ib_send_wr **bad_wr) { @@ -913,7 +937,7 @@ int c4iw_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr, */ if (qhp->wq.flushed) { spin_unlock_irqrestore(&qhp->lock, flag); - err = complete_sq_drain_wr(qhp, wr); + err = complete_sq_drain_wrs(qhp, wr, bad_wr); return err; } num_wrs = t4_sq_avail(&qhp->wq); @@ -1061,7 +1085,7 @@ int c4iw_post_receive(struct ib_qp *ibqp, struct ib_recv_wr *wr, */ if (qhp->wq.flushed) { spin_unlock_irqrestore(&qhp->lock, flag); - complete_rq_drain_wr(qhp, wr); + complete_rq_drain_wrs(qhp, wr); return err; } num_wrs = t4_rq_avail(&qhp->wq);