| Message ID | 1480546112-3099-2-git-send-email-LinoSanfilippo@gmx.de |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Lino Sanfilippo <LinoSanfilippo@gmx.de> Date: Wed, 30 Nov 2016 23:48:32 +0100 > The driver already uses its private lock for synchronization between xmit > and xmit completion handler making the additional use of the xmit_lock > unnecessary. > Furthermore the driver does not set NETIF_F_LLTX resulting in xmit to be > called with the xmit_lock held and then taking the private lock while xmit > completion handler does the reverse, first take the private lock, then the > xmit_lock. > Fix these issues by not taking the xmit_lock in the tx completion handler. > > Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Yeah that could be a nasty deadlock, in fact. Applied, thanks.
diff --git a/drivers/net/ethernet/altera/altera_tse_main.c b/drivers/net/ethernet/altera/altera_tse_main.c index 16c4163..cddc532 100644 --- a/drivers/net/ethernet/altera/altera_tse_main.c +++ b/drivers/net/ethernet/altera/altera_tse_main.c @@ -463,7 +463,6 @@ static int tse_tx_complete(struct altera_tse_private *priv) if (unlikely(netif_queue_stopped(priv->dev) && tse_tx_avail(priv) > TSE_TX_THRESH(priv))) { - netif_tx_lock(priv->dev); if (netif_queue_stopped(priv->dev) && tse_tx_avail(priv) > TSE_TX_THRESH(priv)) { if (netif_msg_tx_done(priv)) @@ -471,7 +470,6 @@ static int tse_tx_complete(struct altera_tse_private *priv) __func__); netif_wake_queue(priv->dev); } - netif_tx_unlock(priv->dev); } spin_unlock(&priv->tx_lock);
The driver already uses its private lock for synchronization between xmit and xmit completion handler making the additional use of the xmit_lock unnecessary. Furthermore the driver does not set NETIF_F_LLTX resulting in xmit to be called with the xmit_lock held and then taking the private lock while xmit completion handler does the reverse, first take the private lock, then the xmit_lock. Fix these issues by not taking the xmit_lock in the tx completion handler. Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> --- drivers/net/ethernet/altera/altera_tse_main.c | 2 -- 1 file changed, 2 deletions(-) Please note that this is only compile tested since I do not have the concerning hardware.