From bb3ab2979fd69db23328691cb10067861df89037 Mon Sep 17 00:00:00 2001 From: Bob Pearson Date: Tue, 13 Oct 2020 12:07:42 -0500 Subject: RDMA/rxe: Compute PSN windows correctly The code which limited the number of unacknowledged PSNs was incorrect. The PSNs are limited to 24 bits and wrap back to zero from 0x00ffffff. The test was computing a 32 bit value which wraps at 32 bits so that qp->req.psn can appear smaller than the limit when it is actually larger. Replace '>' test with psn_compare which is used for other PSN comparisons and correctly handles the 24 bit size. Fixes: 8700e3e7c485 ("Soft RoCE driver") Link: https://lore.kernel.org/r/20201013170741.3590-1-rpearson@hpe.com Signed-off-by: Bob Pearson Signed-off-by: Jason Gunthorpe --- drivers/infiniband/sw/rxe/rxe_req.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/infiniband/sw/rxe/rxe_req.c') diff --git a/drivers/infiniband/sw/rxe/rxe_req.c b/drivers/infiniband/sw/rxe/rxe_req.c index af3923bf0a36..d4917646641a 100644 --- a/drivers/infiniband/sw/rxe/rxe_req.c +++ b/drivers/infiniband/sw/rxe/rxe_req.c @@ -634,7 +634,8 @@ next_wqe: } if (unlikely(qp_type(qp) == IB_QPT_RC && - qp->req.psn > (qp->comp.psn + RXE_MAX_UNACKED_PSNS))) { + psn_compare(qp->req.psn, (qp->comp.psn + + RXE_MAX_UNACKED_PSNS)) > 0)) { qp->req.wait_psn = 1; goto exit; } -- cgit v1.2.3-59-g8ed1b