IB/mthca: memfree completion with error FW bug workaround

Memfree firmware is in rare cases reporting WQE index == base - 1 in receive completion with error, instead of (rq size - 1); base is 0 in mthca. Here is a patch to avoid kernel crash and report a correct WR id in this case. Signed-off-by: Michael S. Tsirkin <[email protected]> Signed-off-by: Roland Dreier <[email protected]>
mrcsosa · Jun 18, 2006 · 4e56ea7 · 4e56ea7
1 parent 13aa6ec
commit 4e56ea7
Showing 1 changed file with 10 additions and 1 deletion.
diff --git a/drivers/infiniband/hw/mthca/mthca_cq.c b/drivers/infiniband/hw/mthca/mthca_cq.c
@@ -540,8 +540,17 @@ static inline int mthca_poll_one(struct mthca_dev *dev,
 		entry->wr_id = srq->wrid[wqe_index];
 		mthca_free_srq_wqe(srq, wqe);
 	} else {
+		s32 wqe;
 		wq = &(*cur_qp)->rq;
-		wqe_index = be32_to_cpu(cqe->wqe) >> wq->wqe_shift;
+		wqe = be32_to_cpu(cqe->wqe);
+		wqe_index = wqe >> wq->wqe_shift;
+               /*
+		* WQE addr == base - 1 might be reported in receive completion
+		* with error instead of (rq size - 1) by Sinai FW 1.0.800 and
+		* Arbel FW 5.1.400.  This bug should be fixed in later FW revs.
+		*/
+		if (unlikely(wqe_index < 0))
+			wqe_index = wq->max - 1;
 		entry->wr_id = (*cur_qp)->wrid[wqe_index];
 	}