From: David Miller <davem@davemloft.net>
To: alex.aring@gmail.com
Cc: alex.bluesman.smirnov@gmail.com, dbaryshkov@gmail.com,
linux-zigbee-devel@lists.sourceforge.net, netdev@vger.kernel.org
Subject: Re: [PATCH net] 6lowpan: add missing fragment list spinlock
Date: Tue, 04 Feb 2014 20:32:03 -0800 (PST) [thread overview]
Message-ID: <20140204.203203.1380460749447396879.davem@davemloft.net> (raw)
In-Reply-To: <1391511473-30000-1-git-send-email-alex.aring@gmail.com>
From: Alexander Aring <alex.aring@gmail.com>
Date: Tue, 4 Feb 2014 11:57:53 +0100
> @@ -197,7 +197,9 @@ static void lowpan_fragment_timer_expired(unsigned long entry_addr)
>
> pr_debug("timer expired for frame with tag %d\n", entry->tag);
>
> + spin_lock_bh(&flist_lock);
> list_del(&entry->list);
> + spin_unlock_bh(&flist_lock);
> dev_kfree_skb(entry->skb);
> kfree(entry);
> }
This will deadlock, because the other code path holding flist_lock calls
del_timer_sync() to wait for this timer to return.
The synchornization in this code is really a big mess.
next prev parent reply other threads:[~2014-02-05 4:32 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-02-04 10:57 [PATCH net] 6lowpan: add missing fragment list spinlock Alexander Aring
2014-02-05 4:32 ` David Miller [this message]
[not found] ` <20140204.203203.1380460749447396879.davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org>
2014-02-05 7:47 ` Alexander Aring
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