diff options
| author | Karl Beldan <karl.beldan@rivierawaves.com> | 2014-11-05 15:32:59 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-11-21 09:23:07 -0800 |
| commit | 64fd58eb83e87feb32a248c01301418e51b0609c (patch) | |
| tree | 74628c5daa87bfb8b294f62983c90d52c43ebfc8 /drivers/net | |
| parent | 7fda9a0901fc790ab8b65fcbb2249ded7c6d9e58 (diff) | |
| download | lwn-64fd58eb83e87feb32a248c01301418e51b0609c.tar.gz lwn-64fd58eb83e87feb32a248c01301418e51b0609c.zip | |
net: mv643xx_eth: reclaim TX skbs only when released by the HW
[ Upstream commit 2c2a9cbd64387d6b70ac5db013e9bfe9412c7354 ]
ATM, txq_reclaim will dequeue and free an skb for each tx desc released
by the hw that has TX_LAST_DESC set. However, in case of TSO, each
hw desc embedding the last part of a segment has TX_LAST_DESC set,
losing the one-to-one 'last skb frag'/'TX_LAST_DESC set' correspondance,
which causes data corruption.
Fix this by checking TX_ENABLE_INTERRUPT instead of TX_LAST_DESC, and
warn when trying to dequeue from an empty txq (which can be symptomatic
of releasing skbs prematurely).
Fixes: 3ae8f4e0b98 ('net: mv643xx_eth: Implement software TSO')
Reported-by: Slawomir Gajzner <slawomir.gajzner@gmail.com>
Reported-by: Julien D'Ascenzio <jdascenzio@yahoo.fr>
Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
Cc: Ian Campbell <ijc@hellion.org.uk>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/ethernet/marvell/mv643xx_eth.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/drivers/net/ethernet/marvell/mv643xx_eth.c b/drivers/net/ethernet/marvell/mv643xx_eth.c index b151a949f352..d44560d1d268 100644 --- a/drivers/net/ethernet/marvell/mv643xx_eth.c +++ b/drivers/net/ethernet/marvell/mv643xx_eth.c @@ -1047,7 +1047,6 @@ static int txq_reclaim(struct tx_queue *txq, int budget, int force) int tx_index; struct tx_desc *desc; u32 cmd_sts; - struct sk_buff *skb; tx_index = txq->tx_used_desc; desc = &txq->tx_desc_area[tx_index]; @@ -1066,19 +1065,22 @@ static int txq_reclaim(struct tx_queue *txq, int budget, int force) reclaimed++; txq->tx_desc_count--; - skb = NULL; - if (cmd_sts & TX_LAST_DESC) - skb = __skb_dequeue(&txq->tx_skb); + if (!IS_TSO_HEADER(txq, desc->buf_ptr)) + dma_unmap_single(mp->dev->dev.parent, desc->buf_ptr, + desc->byte_cnt, DMA_TO_DEVICE); + + if (cmd_sts & TX_ENABLE_INTERRUPT) { + struct sk_buff *skb = __skb_dequeue(&txq->tx_skb); + + if (!WARN_ON(!skb)) + dev_kfree_skb(skb); + } if (cmd_sts & ERROR_SUMMARY) { netdev_info(mp->dev, "tx error\n"); mp->dev->stats.tx_errors++; } - if (!IS_TSO_HEADER(txq, desc->buf_ptr)) - dma_unmap_single(mp->dev->dev.parent, desc->buf_ptr, - desc->byte_cnt, DMA_TO_DEVICE); - dev_kfree_skb(skb); } __netif_tx_unlock_bh(nq); |