From: David Miller <davem@davemloft.net>
To: ying.xue@windriver.com
Cc: jon.maloy@ericsson.com, erik.hugne@ericsson.com,
netdev@vger.kernel.org, tipc-discussion@lists.sourceforge.net
Subject: Re: [PATCH net] tipc: fix lockdep warning when intra-node messages are delivered
Date: Tue, 21 Oct 2014 15:30:25 -0400 (EDT) [thread overview]
Message-ID: <20141021.153025.246696199217285626.davem@davemloft.net> (raw)
In-Reply-To: <1413787595-14700-1-git-send-email-ying.xue@windriver.com>
From: Ying Xue <ying.xue@windriver.com>
Date: Mon, 20 Oct 2014 14:46:35 +0800
> When running tipcTC&tipcTS test suite, below lockdep unsafe locking
> scenario is reported:
...
> When intra-node messages are delivered from one process to another
> process, tipc_link_xmit() doesn't disable BH before it directly calls
> tipc_sk_rcv() on process context to forward messages to destination
> socket. Meanwhile, if messages delivered by remote node arrive at the
> node and their destinations are also the same socket, tipc_sk_rcv()
> running on process context might be preempted by tipc_sk_rcv() running
> BH context. As a result, the latter cannot obtain the socket lock as
> the lock was obtained by the former, however, the former has no chance
> to be run as the latter is owning the CPU now, so headlock happens. To
> avoid it, BH should be always disabled in tipc_sk_rcv().
>
> Signed-off-by: Ying Xue <ying.xue@windriver.com>
> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Applied.
prev parent reply other threads:[~2014-10-21 19:30 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-20 6:46 [PATCH net] tipc: fix lockdep warning when intra-node messages are delivered Ying Xue
2014-10-21 19:30 ` David Miller [this message]
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