From 16ee817e4365cdfe665ae8d6f6bc8f09befa1272 Mon Sep 17 00:00:00 2001 From: Fabrice Gasnier Date: Tue, 4 Nov 2014 17:08:05 +0100 Subject: [PATCH] stmmac: fix stmmac_tx_avail should be called with TX locked stmmac_tx_avail() may lie if used unprotected. It's using cur_tx and dirty_tx index. These index may be already in use by tx_clean when entering xmit routine. So, this should be called locked. This can cause transmit queue to be stuck, with following message: NETDEV WATCHDOG: eth0 (stmmaceth): transmit queue 0 timed out Signed-off-by: Fabrice Gasnier Acked-by: Giuseppe Cavallaro Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 6f77a46c7e2c..bcd8a3414722 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1894,7 +1894,10 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev) unsigned int nopaged_len = skb_headlen(skb); unsigned int enh_desc = priv->plat->enh_desc; + spin_lock(&priv->tx_lock); + if (unlikely(stmmac_tx_avail(priv) < nfrags + 1)) { + spin_unlock(&priv->tx_lock); if (!netif_queue_stopped(dev)) { netif_stop_queue(dev); /* This is a hard error, log it. */ @@ -1903,8 +1906,6 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev) return NETDEV_TX_BUSY; } - spin_lock(&priv->tx_lock); - if (priv->tx_path_in_lpi_mode) stmmac_disable_eee_mode(priv);