diff options
| author | Eric Dumazet <edumazet@google.com> | 2012-06-13 09:45:16 (GMT) |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-06-15 22:30:15 (GMT) |
| commit | bc14786a100cc6a81cd060e8031ec481241b418c (patch) | |
| tree | 344e33a1e1ee80906eb9aaaa339cd3bad257385a | |
| parent | d9cb9bd63eb27ac19f26a8547128c053f43a5da8 (diff) | |
| download | linux-bc14786a100cc6a81cd060e8031ec481241b418c.tar.xz | |
bnx2x: fix panic when TX ring is full
There is a off by one error in the minimal number of BD in
bnx2x_start_xmit() and bnx2x_tx_int() before stopping/resuming tx queue.
A full size GSO packet, with data included in skb->head really needs
(MAX_SKB_FRAGS + 4) BDs, because of bnx2x_tx_split()
This error triggers if BQL is disabled and heavy TCP transmit traffic
occurs.
bnx2x_tx_split() definitely can be called, remove a wrong comment.
Reported-by: Tomas Hruby <thruby@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Eilon Greenstein <eilong@broadcom.com>
Cc: Yaniv Rosner <yanivr@broadcom.com>
Cc: Merav Sicron <meravs@broadcom.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Robert Evans <evansr@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c index cbc56f2..8098eea 100644 --- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c +++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c @@ -190,7 +190,7 @@ int bnx2x_tx_int(struct bnx2x *bp, struct bnx2x_fp_txdata *txdata) if ((netif_tx_queue_stopped(txq)) && (bp->state == BNX2X_STATE_OPEN) && - (bnx2x_tx_avail(bp, txdata) >= MAX_SKB_FRAGS + 3)) + (bnx2x_tx_avail(bp, txdata) >= MAX_SKB_FRAGS + 4)) netif_tx_wake_queue(txq); __netif_tx_unlock(txq); @@ -2516,8 +2516,6 @@ int bnx2x_poll(struct napi_struct *napi, int budget) /* we split the first BD into headers and data BDs * to ease the pain of our fellow microcode engineers * we use one mapping for both BDs - * So far this has only been observed to happen - * in Other Operating Systems(TM) */ static noinline u16 bnx2x_tx_split(struct bnx2x *bp, struct bnx2x_fp_txdata *txdata, @@ -3171,7 +3169,7 @@ netdev_tx_t bnx2x_start_xmit(struct sk_buff *skb, struct net_device *dev) txdata->tx_bd_prod += nbd; - if (unlikely(bnx2x_tx_avail(bp, txdata) < MAX_SKB_FRAGS + 3)) { + if (unlikely(bnx2x_tx_avail(bp, txdata) < MAX_SKB_FRAGS + 4)) { netif_tx_stop_queue(txq); /* paired memory barrier is in bnx2x_tx_int(), we have to keep @@ -3180,7 +3178,7 @@ netdev_tx_t bnx2x_start_xmit(struct sk_buff *skb, struct net_device *dev) smp_mb(); fp->eth_q_stats.driver_xoff++; - if (bnx2x_tx_avail(bp, txdata) >= MAX_SKB_FRAGS + 3) + if (bnx2x_tx_avail(bp, txdata) >= MAX_SKB_FRAGS + 4) netif_tx_wake_queue(txq); } txdata->tx_pkt++; |