From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764147AbZCaXC3 (ORCPT ); Tue, 31 Mar 2009 19:02:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1763360AbZCaXCK (ORCPT ); Tue, 31 Mar 2009 19:02:10 -0400 Received: from fmailhost01.isp.att.net ([207.115.11.51]:36565 "EHLO fmailhost01.isp.att.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757871AbZCaXCJ (ORCPT ); Tue, 31 Mar 2009 19:02:09 -0400 X-Originating-IP: [69.76.240.125] Message-ID: <49D2A0BF.2090901@lwfinger.net> Date: Tue, 31 Mar 2009 18:01:19 -0500 From: Larry Finger User-Agent: Thunderbird 2.0.0.19 (X11/20081227) MIME-Version: 1.0 To: Oliver Neukum CC: linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH 1/2 V2] kaweth: Fix locking to be SMP-safe References: <49d264dd.YwbXLw18YaD1tQqD%Larry.Finger@lwfinger.net> <200903312350.38658.oliver@neukum.org> In-Reply-To: <200903312350.38658.oliver@neukum.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Oliver Neukum wrote: > Am Dienstag 31 März 2009 20:45:49 schrieb Larry Finger: >> On an SMP system, the following message is printed. The patch below gets >> fixes the problem. > > Are you sure it is never called with disabled interrupts? I think not, but all I really know is that the change from spin_lock() to spin_lock_irq() makes the errors go away. I checked a number of drivers to see what their ndo_start_xmit routines do. Most use spin_lock_irq(), but some do no locking. I tried removing the locking, but that resulted in a stall even when I bypassed the faulty router. Larry