iw_cxgb4: only clear the ARMED bit if a notification is needed
authorSteve Wise <swise@opengridcomputing.com>
Thu, 30 Nov 2017 17:41:56 +0000 (09:41 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 17 Jan 2018 08:45:19 +0000 (09:45 +0100)
commit 335ebf6fa35ca1c59b73f76fad19b249d3550e86 upstream.

In __flush_qp(), the CQ ARMED bit was being cleared regardless of
whether any notification is actually needed.  This resulted in the iser
termination logic getting stuck in ib_drain_sq() because the CQ was not
marked ARMED and thus the drain CQE notification wasn't triggered.

This new bug was exposed when this commit was merged:

commit cbb40fadd31c ("iw_cxgb4: only call the cq comp_handler when the
cq is armed")

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/infiniband/hw/cxgb4/qp.c

index c7402f4..74864c4 100644 (file)
@@ -1301,21 +1301,21 @@ static void __flush_qp(struct c4iw_qp *qhp, struct c4iw_cq *rchp,
        spin_unlock_irqrestore(&rchp->lock, flag);
 
        if (schp == rchp) {
-               if (t4_clear_cq_armed(&rchp->cq) &&
-                   (rq_flushed || sq_flushed)) {
+               if ((rq_flushed || sq_flushed) &&
+                   t4_clear_cq_armed(&rchp->cq)) {
                        spin_lock_irqsave(&rchp->comp_handler_lock, flag);
                        (*rchp->ibcq.comp_handler)(&rchp->ibcq,
                                                   rchp->ibcq.cq_context);
                        spin_unlock_irqrestore(&rchp->comp_handler_lock, flag);
                }
        } else {
-               if (t4_clear_cq_armed(&rchp->cq) && rq_flushed) {
+               if (rq_flushed && t4_clear_cq_armed(&rchp->cq)) {
                        spin_lock_irqsave(&rchp->comp_handler_lock, flag);
                        (*rchp->ibcq.comp_handler)(&rchp->ibcq,
                                                   rchp->ibcq.cq_context);
                        spin_unlock_irqrestore(&rchp->comp_handler_lock, flag);
                }
-               if (t4_clear_cq_armed(&schp->cq) && sq_flushed) {
+               if (sq_flushed && t4_clear_cq_armed(&schp->cq)) {
                        spin_lock_irqsave(&schp->comp_handler_lock, flag);
                        (*schp->ibcq.comp_handler)(&schp->ibcq,
                                                   schp->ibcq.cq_context);