From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753168AbYJCOzA (ORCPT ); Fri, 3 Oct 2008 10:55:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751649AbYJCOyw (ORCPT ); Fri, 3 Oct 2008 10:54:52 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:60600 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751092AbYJCOyw (ORCPT ); Fri, 3 Oct 2008 10:54:52 -0400 Date: Fri, 3 Oct 2008 07:52:38 -0700 (PDT) From: Linus Torvalds To: Christian Borntraeger cc: Thomas Gleixner , linux-kernel@vger.kernel.org, Jesse Brandeburg Subject: Re: [regression] Latest git has WARN_ON storm with e1000e driver In-Reply-To: <200810031041.49350.borntraeger@de.ibm.com> Message-ID: References: <200810031041.49350.borntraeger@de.ibm.com> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 3 Oct 2008, Christian Borntraeger wrote: > > This is caused by holding a spinlock (__driver_attach) and checking for > preempt_count (e1000_acquire_swflag_ich8lan). Which spinlock is it? It sure shouldn't be anything in the generic drievr layer: __driver_attach takes a lock, but it's a semaphore (dev->sem), not a spinlock. In fact, al lot of drivers will sleep or do allocations, so if the driver layer were to call the probe function with a spinlock held, things would be really broken. The callchain has "spin_lock_irqsave" in it, but that's stale stack data. Linus