sky2: Avoid transmits during sky2_down()
This patch supersedes my previous patch "sky2: Avoid transmitting
during sky2_restart".
I have reworked the patch to avoid crashes during both sky2_restart()
and sky2_set_ringparam().
Without this patch, the sky2 driver can be crashed by doing:
# pktgen eth1 & (transmit many packets on eth1)
# ethtool -G eth1 tx 510
I am aware you object to storing extra state, but I can't see a way
around this. Without remembering that we're restarting,
netif_wake_queue() is called in the ISR from sky2_tx_complete(), and
netif_tx_lock() is used in sky2_tx_done(). If anybody can see a way
around this, please let me know.
Signed-off-by: Mike McCormack <mikem@ring3k.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index 3550c5d..0a551d8 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -1488,6 +1488,8 @@
sky2_set_vlan_mode(hw, port, sky2->vlgrp != NULL);
#endif
+ sky2->restarting = 0;
+
err = sky2_rx_start(sky2);
if (err)
goto err_out;
@@ -1500,6 +1502,9 @@
sky2_set_multicast(dev);
+ /* wake queue incase we are restarting */
+ netif_wake_queue(dev);
+
if (netif_msg_ifup(sky2))
printk(KERN_INFO PFX "%s: enabling interface\n", dev->name);
return 0;
@@ -1533,6 +1538,8 @@
/* Number of list elements available for next tx */
static inline int tx_avail(const struct sky2_port *sky2)
{
+ if (unlikely(sky2->restarting))
+ return 0;
return sky2->tx_pending - tx_dist(sky2->tx_cons, sky2->tx_prod);
}
@@ -1818,6 +1825,10 @@
if (netif_msg_ifdown(sky2))
printk(KERN_INFO PFX "%s: disabling interface\n", dev->name);
+ /* explicitly shut off tx incase we're restarting */
+ sky2->restarting = 1;
+ netif_tx_disable(dev);
+
/* Force flow control off */
sky2_write8(hw, SK_REG(port, GMAC_CTRL), GMC_PAUSE_OFF);
@@ -2359,7 +2370,7 @@
{
struct sky2_port *sky2 = netdev_priv(dev);
- if (netif_running(dev)) {
+ if (likely(netif_running(dev) && !sky2->restarting)) {
netif_tx_lock(dev);
sky2_tx_complete(sky2, last);
netif_tx_unlock(dev);
@@ -4283,6 +4294,7 @@
spin_lock_init(&sky2->phy_lock);
sky2->tx_pending = TX_DEF_PENDING;
sky2->rx_pending = RX_DEF_PENDING;
+ sky2->restarting = 0;
hw->dev[port] = dev;
diff --git a/drivers/net/sky2.h b/drivers/net/sky2.h
index b5549c9..4486b06 100644
--- a/drivers/net/sky2.h
+++ b/drivers/net/sky2.h
@@ -2051,6 +2051,7 @@
u8 duplex; /* DUPLEX_HALF, DUPLEX_FULL */
u8 rx_csum;
u8 wol;
+ u8 restarting;
enum flow_control flow_mode;
enum flow_control flow_status;