Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756879Ab0HPW1V (ORCPT ); Mon, 16 Aug 2010 18:27:21 -0400 Received: from he.sipsolutions.net ([78.46.109.217]:42025 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756763Ab0HPW1U (ORCPT ); Mon, 16 Aug 2010 18:27:20 -0400 Subject: Re: lockdep false positive? -- firewire-core transaction timer vs. scsi-core host lock From: Johannes Berg To: Peter Zijlstra Cc: Stefan Richter , linux1394-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org In-Reply-To: <1281994939.1926.2075.camel@laptop> References: <1281994939.1926.2075.camel@laptop> Content-Type: text/plain; charset="UTF-8" Date: Tue, 17 Aug 2010 00:27:13 +0200 Message-ID: <1281997633.3683.50.camel@jlt3.sipsolutions.net> Mime-Version: 1.0 X-Mailer: Evolution 2.30.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 995 Lines: 34 On Mon, 2010-08-16 at 23:42 +0200, Peter Zijlstra wrote: > softirq: > spin_lock(&t->split_timeout_timer); > > IRQ: > spin_lock(&(shost->host_lock)->rlock); > spin_lock(&t->split_timeout_timer); Actually, I think it's worried that you could have CPU 0 CPU 1 softirq: softirq: spin_lock(timer) spin_lock(rlock) irq: spin_lock(rlock) spin_lock(timer) [still in softirq] because it has previously seen the nesting that I put on CPU 1, and now found that the timer "lock" is used with interrupts enabled. At least that's a scenario I could understand? I'm convinced it's a false positive though, question is how to shut it up :-) johannes -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/