From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932224AbeENNer (ORCPT ); Mon, 14 May 2018 09:34:47 -0400 Received: from mx2.suse.de ([195.135.220.15]:52534 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752142AbeENNep (ORCPT ); Mon, 14 May 2018 09:34:45 -0400 Date: Mon, 14 May 2018 15:34:42 +0200 From: Johannes Thumshirn To: "Paul E. McKenney" Cc: Christoph Hellwig , Keith Busch , Sagi Grimberg , Linux Kernel Mailinglist , Linux NVMe Mailinglist , Hannes Reinecke , Christoph Hellwig Subject: Re: [PATCH] nvme: fix lockdep warning in nvme_mpath_clear_current_path Message-ID: <20180514133442.dyvveuxkaeithb4r@linux-x5ow.site> References: <20180514121312.13624-1-jthumshirn@suse.de> <20180514124230.GA654@infradead.org> <20180514133105.GU26088@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20180514133105.GU26088@linux.vnet.ibm.com> User-Agent: NeoMutt/20170912 (1.9.0) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 14, 2018 at 06:31:05AM -0700, Paul E. McKenney wrote: > If you are just looking at the value of an RCU-protected pointer, then > using rcu_access_pointer() will cause RCU to just read out the value > and otherwise keeps its mouth shut. > > If you use rcu_access_pointer() and later dereference the value without > protection, you will of course get what you deserve, good and hard. ;-) Thanks Paul. Christoph, I'll be sending the v2 probably tomorrow as I have more lockdep fixes for nvme in the pipe and I'll send them out as a complete series. -- Johannes Thumshirn Storage jthumshirn@suse.de +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg) Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850