[PATCH for 2.6.25] RDMA/cxgb3: Program hardware IRD with correct value

From: Roland Dreier
Date: Fri Mar 28 2008 - 13:28:29 EST


Because of a typo in iwch_accept_cr(), the cxgb3 connection handling
code programs the hardware IRD (incoming RDMA read queue depth) with
the value that is passed in for the ORD (outgoing RDMA read queue
depth). In particular this means that if an application passes in IRD
> 0 and ORD = 0 (which is a completely sane and valid thing to do for
an app that expects only incoming RDMA read requests), then the
hardware will end up programmed with IRD = 0 and the app will fail in
a mysterious way.

Fix this by using "ep->ird" instead of "ep->ord" in the intended place.

Signed-off-by: Roland Dreier <rolandd@xxxxxxxxx>
Acked-by: Steve Wise <swise@xxxxxxxxxxxxxxxxxxxxx>
---
Linus, please add this for 2.6.25 if possible -- it's a trivial,
"obviously correct" fix that is very low risk and fixes real apps.

Thanks,
Roland

diff --git a/drivers/infiniband/hw/cxgb3/iwch_cm.c b/drivers/infiniband/hw/cxgb3/iwch_cm.c
index 320f2b6..99f2f2a 100644
--- a/drivers/infiniband/hw/cxgb3/iwch_cm.c
+++ b/drivers/infiniband/hw/cxgb3/iwch_cm.c
@@ -1745,7 +1745,7 @@ int iwch_accept_cr(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param)

/* bind QP to EP and move to RTS */
attrs.mpa_attr = ep->mpa_attr;
- attrs.max_ird = ep->ord;
+ attrs.max_ird = ep->ird;
attrs.max_ord = ep->ord;
attrs.llp_stream_handle = ep;
attrs.next_state = IWCH_QP_STATE_RTS;
--
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