[PATCH 4.19 011/139] lan743x: fix return value for lan743x_tx_napi_poll

From: Greg Kroah-Hartman
Date: Tue Dec 04 2018 - 06:33:45 EST


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

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

From: Bryan Whitehead <Bryan.Whitehead@xxxxxxxxxxxxx>

[ Upstream commit cc5922054131f9abefdc0622ae64fc55e6b2671d ]

The lan743x driver, when under heavy traffic load, has been noticed
to sometimes hang, or cause a kernel panic.

Debugging reveals that the TX napi poll routine was returning
the wrong value, 'weight'. Most other drivers return 0.
And call napi_complete, instead of napi_complete_done.

Additionally when creating the tx napi poll routine.
Changed netif_napi_add, to netif_tx_napi_add.

Updates for v3:
changed 'fixes' tag to match defined format

Updates for v2:
use napi_complete, instead of napi_complete_done in
lan743x_tx_napi_poll
use netif_tx_napi_add, instead of netif_napi_add for
registration of tx napi poll routine

fixes: 23f0703c125b ("lan743x: Add main source files for new lan743x driver")
Signed-off-by: Bryan Whitehead <Bryan.Whitehead@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/microchip/lan743x_main.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

--- a/drivers/net/ethernet/microchip/lan743x_main.c
+++ b/drivers/net/ethernet/microchip/lan743x_main.c
@@ -1675,7 +1675,7 @@ static int lan743x_tx_napi_poll(struct n
netif_wake_queue(adapter->netdev);
}

- if (!napi_complete_done(napi, weight))
+ if (!napi_complete(napi))
goto done;

/* enable isr */
@@ -1684,7 +1684,7 @@ static int lan743x_tx_napi_poll(struct n
lan743x_csr_read(adapter, INT_STS);

done:
- return weight;
+ return 0;
}

static void lan743x_tx_ring_cleanup(struct lan743x_tx *tx)
@@ -1873,9 +1873,9 @@ static int lan743x_tx_open(struct lan743
tx->vector_flags = lan743x_intr_get_vector_flags(adapter,
INT_BIT_DMA_TX_
(tx->channel_number));
- netif_napi_add(adapter->netdev,
- &tx->napi, lan743x_tx_napi_poll,
- tx->ring_size - 1);
+ netif_tx_napi_add(adapter->netdev,
+ &tx->napi, lan743x_tx_napi_poll,
+ tx->ring_size - 1);
napi_enable(&tx->napi);

data = 0;