[TG3]: Flush tg3_reset_task()
Make sure tg3_reset_task() is flushed in the close and suspend paths
as noted by Jeff Garzik.
In the close path, calling flush_scheduled_work() may cause deadlock
if linkwatch_event() is on the workqueue. linkwatch_event() will try
to get the rtnl_lock() which is already held by tg3_close(). So
instead, we set a flag in tg3_reset_task() and tg3_close() polls
the flag until it is cleared.
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 f2d1daf..6fb29ca 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -3482,6 +3482,17 @@
struct tg3 *tp = _data;
unsigned int restart_timer;
+ tg3_full_lock(tp, 0);
+ tp->tg3_flags |= TG3_FLAG_IN_RESET_TASK;
+
+ if (!netif_running(tp->dev)) {
+ tp->tg3_flags &= ~TG3_FLAG_IN_RESET_TASK;
+ tg3_full_unlock(tp);
+ return;
+ }
+
+ tg3_full_unlock(tp);
+
tg3_netif_stop(tp);
tg3_full_lock(tp, 1);
@@ -3494,10 +3505,12 @@
tg3_netif_start(tp);
- tg3_full_unlock(tp);
-
if (restart_timer)
mod_timer(&tp->timer, jiffies + 1);
+
+ tp->tg3_flags &= ~TG3_FLAG_IN_RESET_TASK;
+
+ tg3_full_unlock(tp);
}
static void tg3_tx_timeout(struct net_device *dev)
@@ -6786,6 +6799,13 @@
{
struct tg3 *tp = netdev_priv(dev);
+ /* Calling flush_scheduled_work() may deadlock because
+ * linkwatch_event() may be on the workqueue and it will try to get
+ * the rtnl_lock which we are holding.
+ */
+ while (tp->tg3_flags & TG3_FLAG_IN_RESET_TASK)
+ msleep(1);
+
netif_stop_queue(dev);
del_timer_sync(&tp->timer);
@@ -10880,6 +10900,7 @@
if (dev) {
struct tg3 *tp = netdev_priv(dev);
+ flush_scheduled_work();
unregister_netdev(dev);
if (tp->regs) {
iounmap(tp->regs);
@@ -10901,6 +10922,7 @@
if (!netif_running(dev))
return 0;
+ flush_scheduled_work();
tg3_netif_stop(tp);
del_timer_sync(&tp->timer);