[PATCH AUTOSEL 4.19 086/123] lan743x: fix return value for lan743x_tx_napi_poll

From: Sasha Levin
Date: Wed Dec 05 2018 - 05:07:31 EST


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: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/microchip/lan743x_main.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
index 001b5f714c1b..5c3ac70abeca 100644
--- 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 napi_struct *napi, int weight)
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 napi_struct *napi, int weight)
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 lan743x_tx *tx)
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;
--
2.17.1