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Date: Mon, 15 Oct 2007 15:21:26 -0700 (PDT)
Message-Id: <20071015.152126.85410587.davem@davemloft.net>
To: mingo@elte.hu
Cc: linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
       shemminger@linux-foundation.org, jgarzik@pobox.com
Subject: Re: WARNING: at net/core/dev.c:2161 net_rx_action()
From: David Miller <davem@davemloft.net>
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From: Ingo Molnar <mingo@elte.hu>
Date: Tue, 16 Oct 2007 00:07:20 +0200

> looking at the dev.c code - can napi_struct->weight be zero 
> legitimately? If yes then the 0 gets passed to the driver and the driver 
> would return 1 - violating the assertion.

I touched upon this in another reply.

For forcedeth it should never be zero, it gets set in
netif_napi_add() to RX_WORK_PER_LOOP which is unconditionally
defined to 64.

Afterwards napi->weight should never be modified and that is
what is passed into n->poll().

Perhaps some memory scribble is causing it to be zero'd.