Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751384Ab0KCVTB (ORCPT ); Wed, 3 Nov 2010 17:19:01 -0400 Received: from isilmar-3.linta.de ([188.40.101.200]:50470 "EHLO linta.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750883Ab0KCVS7 (ORCPT ); Wed, 3 Nov 2010 17:18:59 -0400 Date: Wed, 3 Nov 2010 22:18:55 +0100 From: Dominik Brodowski To: Linus Torvalds Cc: "Rafael J. Wysocki" , Linux-pm mailing list , LKML Subject: Re: [linux-pm] [GIT PULL] One more power management fix for 2.6.37 Message-ID: <20101103211855.GA29721@isilmar-3.linta.de> Mail-Followup-To: Linus Torvalds , "Rafael J. Wysocki" , Linux-pm mailing list , LKML References: <201010292358.27975.rjw@sisk.pl> <201011030356.13878.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 913 Lines: 25 > There's apparently an ordering problem with dpm_list_mtx and > socket->skt_mutex. Lockdep details appended. > > Dominik, Rafael? What's the proper locking order here, and > how do we fix this? Thanks for noting this; let's see: - We add a PCMCIA device holding skt_mutex, therefore we have the ordering (1) skt_mutex -> (2) dpm_list_mtx - If we're suspending, dpm_list_mtx is held, but we need to acquire skt_mutex as we modify some data being protected by skt_mutex (1) dpm_list_mtx -> (2) skt_mutex Rafael, any idea on how to solve this? How do other subsystems handle such an issue? Do they call device_add() with no locks held at all? Best, Dominik -- 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/