Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755155AbXLHRUR (ORCPT ); Sat, 8 Dec 2007 12:20:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752418AbXLHRUF (ORCPT ); Sat, 8 Dec 2007 12:20:05 -0500 Received: from gateway-1237.mvista.com ([63.81.120.158]:24898 "EHLO gateway-1237.mvista.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752334AbXLHRUC (ORCPT ); Sat, 8 Dec 2007 12:20:02 -0500 Subject: Re: lockdep problem conversion semaphore->mutex (dev->sem) From: Daniel Walker To: Peter Zijlstra Cc: Remy Bohmer , Ingo Molnar , Steven Rostedt , linux-kernel , Dave Chinner In-Reply-To: <1197133910.6353.33.camel@lappy> References: <3efb10970712071502p4db9c58ck623c377172ead4b2@mail.gmail.com> <1197116185.31440.1.camel@twins> <1197132792.1568.162.camel@jnielson-xp.ddns.mvista.com> <1197133910.6353.33.camel@lappy> Content-Type: text/plain Date: Sat, 08 Dec 2007 09:06:16 -0800 Message-Id: <1197133577.1568.166.camel@jnielson-xp.ddns.mvista.com> Mime-Version: 1.0 X-Mailer: Evolution 2.10.3 (2.10.3-4.fc7) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 782 Lines: 20 On Sat, 2007-12-08 at 18:11 +0100, Peter Zijlstra wrote: > > It must be the locking in __driver_attach(), taking dev->parent->sem > > then taking dev->sem .. Assuming those are different structures, why > > does lockdep trigger? > > They aren't different, parent is a struct device again. It's different memory tho .. I wasn't sure how to term that .. The locks are in two different memory location so it couldn't be recursive .. I'm only asking for my own understanding .. I don't mind inspecting potentially bad locking .. Daniel -- 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/