[NETPOLL] netconsole: fix soft lockup when removing module
#1
Until kernel ver. 2.6.21 (including) cancel_rearming_delayed_work()
required a work function should always (unconditionally) rearm with
delay > 0 - otherwise it would endlessly loop. This patch replaces
this function with cancel_delayed_work(). Later kernel versions don't
require this, so here it's only for uniformity.
#2
After deleting a timer in cancel_[rearming_]delayed_work() there could
stay a last skb queued in npinfo->txq causing a memory leak after
kfree(npinfo).
Initial patch & testing by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Jarek Poplawski <jarkao2@o2.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index f8e74e5..cf40ff9 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -72,7 +72,8 @@
netif_tx_unlock(dev);
local_irq_restore(flags);
- schedule_delayed_work(&npinfo->tx_work, HZ/10);
+ if (atomic_read(&npinfo->refcnt))
+ schedule_delayed_work(&npinfo->tx_work, HZ/10);
return;
}
netif_tx_unlock(dev);
@@ -785,9 +786,15 @@
if (atomic_dec_and_test(&npinfo->refcnt)) {
skb_queue_purge(&npinfo->arp_tx);
skb_queue_purge(&npinfo->txq);
- cancel_rearming_delayed_work(&npinfo->tx_work);
+ cancel_delayed_work(&npinfo->tx_work);
flush_scheduled_work();
+ /* clean after last, unfinished work */
+ if (!skb_queue_empty(&npinfo->txq)) {
+ struct sk_buff *skb;
+ skb = __skb_dequeue(&npinfo->txq);
+ kfree_skb(skb);
+ }
kfree(npinfo);
}
}