[PATCH 4.14 21/71] RDMA/bnxt_re: Fix Send Work Entry state check while polling completions

From: Greg Kroah-Hartman
Date: Thu Jan 16 2020 - 18:35:59 EST


From: Selvin Xavier <selvin.xavier@xxxxxxxxxxxx>

commit c5275723580922e5f3264f96751337661a153c7d upstream.

Some adapters need a fence Work Entry to handle retransmission. Currently
the driver checks for this condition, only if the Send queue entry is
signalled. Implement the condition check, irrespective of the signalled
state of the Work queue entries

Failure to add the fence can result in access to memory that is already
marked as completed, triggering data corruption, transmission failure,
IOMMU failures, etc.

Fixes: 9152e0b722b2 ("RDMA/bnxt_re: HW workarounds for handling specific conditions")
Link: https://lore.kernel.org/r/1574671174-5064-3-git-send-email-selvin.xavier@xxxxxxxxxxxx
Signed-off-by: Selvin Xavier <selvin.xavier@xxxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/infiniband/hw/bnxt_re/qplib_fp.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

--- a/drivers/infiniband/hw/bnxt_re/qplib_fp.c
+++ b/drivers/infiniband/hw/bnxt_re/qplib_fp.c
@@ -2024,13 +2024,13 @@ static int bnxt_qplib_cq_process_req(str
bnxt_qplib_mark_qp_error(qp);
bnxt_qplib_unlock_buddy_cq(qp, cq);
} else {
+ /* Before we complete, do WA 9060 */
+ if (do_wa9060(qp, cq, cq_cons, sw_sq_cons,
+ cqe_sq_cons)) {
+ *lib_qp = qp;
+ goto out;
+ }
if (swq->flags & SQ_SEND_FLAGS_SIGNAL_COMP) {
- /* Before we complete, do WA 9060 */
- if (do_wa9060(qp, cq, cq_cons, sw_sq_cons,
- cqe_sq_cons)) {
- *lib_qp = qp;
- goto out;
- }
cqe->status = CQ_REQ_STATUS_OK;
cqe++;
(*budget)--;