[TG3]: Fix irq_sync race condition.
Gagan Arneja <gaagaan@gmail.com> pointed out that tg3_reset_task()
could potentially race with another thread calling tg3_full_lock()
such as the ethtool_set_xxx() functions. This may trigger the
BUG_ON() in tg3_irq_quiesce() or cause the irq_sync flag to be out-
of-sync.
I think the easiest way to fix this is to get the tp->lock first
before setting the irq_sync flag. This is safe to do because the
tp->lock is never grabbed by the irq handler. This change will
guarantee that the irq_sync flag updates will be serialized. We also
have to change one spot to call tg3_netif_start() (which clears the
irq_sync flag) before releasing the tp->lock.
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index 3a43426..314f5cf 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -3512,9 +3512,9 @@
*/
static inline void tg3_full_lock(struct tg3 *tp, int irq_sync)
{
+ spin_lock_bh(&tp->lock);
if (irq_sync)
tg3_irq_quiesce(tp);
- spin_lock_bh(&tp->lock);
}
static inline void tg3_full_unlock(struct tg3 *tp)
@@ -9116,10 +9116,10 @@
/* Update RX_MODE_KEEP_VLAN_TAG bit in RX_MODE register. */
__tg3_set_rx_mode(dev);
- tg3_full_unlock(tp);
-
if (netif_running(dev))
tg3_netif_start(tp);
+
+ tg3_full_unlock(tp);
}
#endif