From: Jarek Poplawski Date: Fri, 29 Jun 2007 05:11:47 +0000 (-0700) Subject: [NETPOLL] netconsole: fix soft lockup when removing module X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=17200811cf539b9107a99a39bf71ba3567966285;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git [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 Signed-off-by: Jarek Poplawski Signed-off-by: Andrew Morton Signed-off-by: David S. Miller --- diff --git a/net/core/netpoll.c b/net/core/netpoll.c index f8e74e511ce6..cf40ff91ac01 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -72,7 +72,8 @@ static void queue_process(struct work_struct *work) 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 @@ void netpoll_cleanup(struct netpoll *np) 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); } }