CQ overflow detection needs to read the gen bit and the timestamp in one read operation. Otherwise false overflows can result.
Signed-off-by: Steve Wise <[email protected]> --- drivers/infiniband/hw/cxgb4/t4.h | 7 ++++--- 1 files changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/infiniband/hw/cxgb4/t4.h b/drivers/infiniband/hw/cxgb4/t4.h index 7f04dc5..d0e8af3 100644 --- a/drivers/infiniband/hw/cxgb4/t4.h +++ b/drivers/infiniband/hw/cxgb4/t4.h @@ -502,11 +502,12 @@ static inline int t4_valid_cqe(struct t4_cq *cq, struct t4_cqe *cqe) static inline int t4_next_hw_cqe(struct t4_cq *cq, struct t4_cqe **cqe) { int ret = 0; + u64 bits_type_ts = be64_to_cpu(cq->queue[cq->cidx].bits_type_ts); - if (t4_valid_cqe(cq, &cq->queue[cq->cidx])) { + if (G_CQE_GENBIT(bits_type_ts) == cq->gen) { *cqe = &cq->queue[cq->cidx]; - cq->timestamp = CQE_TS(*cqe); - } else if (CQE_TS(&cq->queue[cq->cidx]) > cq->timestamp) + cq->timestamp = G_CQE_TS(bits_type_ts); + } else if (G_CQE_TS(bits_type_ts) > cq->timestamp) ret = -EOVERFLOW; else ret = -ENODATA; -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
