[PATCH 3.14 74/84] bna: fix interrupts storm caused by erroneous packets

From: Greg Kroah-Hartman
Date: Tue Sep 29 2015 - 11:30:52 EST


3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Ivan Vecera <ivecera@xxxxxxxxxx>

[ Upstream commit ade4dc3e616e33c80d7e62855fe1b6f9895bc7c3 ]

The commit "e29aa33 bna: Enable Multi Buffer RX" moved packets counter
increment from the beginning of the NAPI processing loop after the check
for erroneous packets so they are never accounted. This counter is used
to inform firmware about number of processed completions (packets).
As these packets are never acked the firmware fires IRQs for them again
and again.

Fixes: e29aa33 ("bna: Enable Multi Buffer RX")
Signed-off-by: Ivan Vecera <ivecera@xxxxxxxxxx>
Acked-by: Rasesh Mody <rasesh.mody@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/brocade/bna/bnad.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/ethernet/brocade/bna/bnad.c
+++ b/drivers/net/ethernet/brocade/bna/bnad.c
@@ -674,6 +674,7 @@ bnad_cq_process(struct bnad *bnad, struc
if (!next_cmpl->valid)
break;
}
+ packets++;

/* TODO: BNA_CQ_EF_LOCAL ? */
if (unlikely(flags & (BNA_CQ_EF_MAC_ERROR |
@@ -690,7 +691,6 @@ bnad_cq_process(struct bnad *bnad, struc
else
bnad_cq_setup_skb_frags(rcb, skb, sop_ci, nvecs, len);

- packets++;
rcb->rxq->rx_packets++;
rcb->rxq->rx_bytes += totlen;
ccb->bytes_per_intr += totlen;


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