From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758170AbYE0NO4 (ORCPT ); Tue, 27 May 2008 09:14:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757396AbYE0NOr (ORCPT ); Tue, 27 May 2008 09:14:47 -0400 Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:47594 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1757300AbYE0NOq (ORCPT ); Tue, 27 May 2008 09:14:46 -0400 Date: Tue, 27 May 2008 06:14:42 -0700 (PDT) Message-Id: <20080527.061442.193726441.davem@davemloft.net> To: komurojun-mbn@nifty.com Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PLEASE REVERT] "Add a WARN_ON_ONCE" at net/sched/sch_generic.c: From: David Miller In-Reply-To: <20080527213424.125e15dc.komurojun-mbn@nifty.com> References: <20080525112308.03a5fda7.komurojun-mbn@nifty.com> <20080525.051032.186144643.davem@davemloft.net> <20080527213424.125e15dc.komurojun-mbn@nifty.com> X-Mailer: Mew version 5.2 on Emacs 22.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Komuro Date: Tue, 27 May 2008 21:34:24 +0900 > I think the transmit timeout indicates > that the cable is not connected or the irq is conflict. The MAC of the chip transmits and ACKs the packet in the hardware even if the link is down. The packet is simply dropped. Also, when the link goes down, the driver should mark the device as such. In such a state, the generic networking does not pass new packets to the driver. Therefore, transmit timeouts in this case are a hardware or driver error. If there is an IRQ issue, that is an error that'd we would like to have as much information as possible to diagnose. So the warning is still entirely appropriate. I sense that you are seeing this warning triggered, and if so I would suggest that you investigate it fully as it should not be happening under normal circumstances.