From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike McCormack <mikem@ring3k.org>
Subject: Re: [PATCH] Fix a race between sky2_down and sky2_poll.
Date: Tue, 02 Jun 2009 15:29:50 +0900
Message-ID: <4A24C6DE.1040301@ring3k.org>
References: <392fb48f0906011840n4914ef32x8aa316358b2ceacc@mail.gmail.com> <20090601210728.2be1a903@nehalam>
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Cc: netdev@vger.kernel.org
To: Stephen Hemminger <shemminger@linux-foundation.org>
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Stephen Hemminger wrote:

>> -	/* Make sure no packets are pending */
>> -	napi_synchronize(&hw->napi);

> Down is also used during suspend/resume and changing MTU so this needs
> more inspection.

Could it be that the real problem is with the non-SMP case for 
napi_synchronize()?  The comment in include/linux/netdevice.h claims 
that napi_synchronize() "Waits till any outstanding processing 
completes..." but the implementation for non-SMP is just a barrier()...

Mike