From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] pch_gbe: fix transmit races
Date: Tue, 15 May 2012 13:43:00 -0400 (EDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Mon, 14 May 2012 21:26:06 +0200

> From: Eric Dumazet <edumazet@google.com>
> 
> Andy reported pch_gbe triggered "NETDEV WATCHDOG" errors.
> 
> May 11 11:06:09 kontron kernel: WARNING: at net/sched/sch_generic.c:261
> dev_watchdog+0x1ec/0x200() (Not tainted)
> May 11 11:06:09 kontron kernel: Hardware name: N/A
> May 11 11:06:09 kontron kernel: NETDEV WATCHDOG: eth0 (pch_gbe):
> transmit queue 0 timed out
> 
> It seems pch_gbe has a racy tx path (races with TX completion path)
> 
> Remove tx_queue_lock lock since it has no purpose, we must use tx_lock
> instead.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Reported-by: Andy Cress <andy.cress@us.kontron.com>
> Tested-by: Andy Cress <andy.cress@us.kontron.com>

Applied.