diff options
| author | Somnath Kotur <somnath.kotur@broadcom.com> | 2017-11-06 08:07:29 -0800 |
|---|---|---|
| committer | Doug Ledford <dledford@redhat.com> | 2017-11-13 15:53:57 -0500 |
| commit | 9b40183c08e48f1d26d06d39f29808c9c6037561 (patch) | |
| tree | 377a0f40b396d2b98a65ae0c2c7979527576b1bd | |
| parent | 685894dd9bd03b92803fbc72565789713f067d4c (diff) | |
RDMA/bnxt_re: Add memory barriers when processing CQ/EQ entries
The code determines if the next ring entry is valid before proceeding
further to read the rest of the entry. The CPU can re-order and read
the rest of the entry first, possibly reading a stale entry, if DMA
of a new entry happens right after reading it.
Signed-off-by: Somnath Kotur <somnath.kotur@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
| -rw-r--r-- | drivers/infiniband/hw/bnxt_re/qplib_fp.c | 21 | ||||
| -rw-r--r-- | drivers/infiniband/hw/bnxt_re/qplib_rcfw.c | 4 |
2 files changed, 25 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/bnxt_re/qplib_fp.c b/drivers/infiniband/hw/bnxt_re/qplib_fp.c index a82044dacce0..31ea9f43f7d3 100644 --- a/drivers/infiniband/hw/bnxt_re/qplib_fp.c +++ b/drivers/infiniband/hw/bnxt_re/qplib_fp.c @@ -292,6 +292,12 @@ static void bnxt_qplib_service_nq(unsigned long data) if (!NQE_CMP_VALID(nqe, raw_cons, hwq->max_elements)) break; + /* + * The valid test of the entry must be done first before + * reading any further. + */ + dma_rmb(); + type = le16_to_cpu(nqe->info10_type) & NQ_BASE_TYPE_MASK; switch (type) { case NQ_BASE_TYPE_CQ_NOTIFICATION: @@ -1113,6 +1119,11 @@ static void __clean_cq(struct bnxt_qplib_cq *cq, u64 qp) hw_cqe = &hw_cqe_ptr[CQE_PG(i)][CQE_IDX(i)]; if (!CQE_CMP_VALID(hw_cqe, i, cq_hwq->max_elements)) continue; + /* + * The valid test of the entry must be done first before + * reading any further. + */ + dma_rmb(); switch (hw_cqe->cqe_type_toggle & CQ_BASE_CQE_TYPE_MASK) { case CQ_BASE_CQE_TYPE_REQ: case CQ_BASE_CQE_TYPE_TERMINAL: @@ -1896,6 +1907,11 @@ static int do_wa9060(struct bnxt_qplib_qp *qp, struct bnxt_qplib_cq *cq, /* If the next hwcqe is VALID */ if (CQE_CMP_VALID(peek_hwcqe, peek_raw_cq_cons, cq->hwq.max_elements)) { + /* + * The valid test of the entry must be done first before + * reading any further. + */ + dma_rmb(); /* If the next hwcqe is a REQ */ if ((peek_hwcqe->cqe_type_toggle & CQ_BASE_CQE_TYPE_MASK) == @@ -2440,6 +2456,11 @@ int bnxt_qplib_poll_cq(struct bnxt_qplib_cq *cq, struct bnxt_qplib_cqe *cqe, if (!CQE_CMP_VALID(hw_cqe, raw_cons, cq->hwq.max_elements)) break; + /* + * The valid test of the entry must be done first before + * reading any further. + */ + dma_rmb(); /* From the device's respective CQE format to qplib_wc*/ switch (hw_cqe->cqe_type_toggle & CQ_BASE_CQE_TYPE_MASK) { case CQ_BASE_CQE_TYPE_REQ: diff --git a/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c b/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c index a7b5de3e193c..bb5574adf195 100644 --- a/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c +++ b/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c @@ -359,6 +359,10 @@ static void bnxt_qplib_service_creq(unsigned long data) creqe = &creq_ptr[get_creq_pg(sw_cons)][get_creq_idx(sw_cons)]; if (!CREQ_CMP_VALID(creqe, raw_cons, creq->max_elements)) break; + /* The valid test of the entry must be done first before + * reading any further. + */ + dma_rmb(); type = creqe->type & CREQ_BASE_TYPE_MASK; switch (type) { |