From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Paul E. McKenney" Subject: Re: [BUG] commit a9b3cd7f32 is a mess Date: Thu, 12 Jan 2012 09:12:01 -0800 Message-ID: <20120112171201.GC2419@linux.vnet.ibm.com> References: <1326376603.2950.14.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> Reply-To: paulmck@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Stephen Hemminger , netdev To: Eric Dumazet Return-path: Received: from e7.ny.us.ibm.com ([32.97.182.137]:37764 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754543Ab2ALROe (ORCPT ); Thu, 12 Jan 2012 12:14:34 -0500 Received: from /spool/local by e7.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 12 Jan 2012 12:14:33 -0500 Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by d01relay04.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q0CHDOBf279724 for ; Thu, 12 Jan 2012 12:13:24 -0500 Received: from d03av01.boulder.ibm.com (loopback [127.0.0.1]) by d03av01.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q0CHC2aG014100 for ; Thu, 12 Jan 2012 10:12:02 -0700 Content-Disposition: inline In-Reply-To: <1326376603.2950.14.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, Jan 12, 2012 at 02:56:43PM +0100, Eric Dumazet wrote: > commit a9b3cd7f32 (rcu: convert uses of rcu_assign_pointer(x, NULL) to > RCU_INIT_POINTER) is complete garbage. > > Real content of this commit doesnt reflect Changelog claim. > > I found this while trying to understand a 3.2 regression in IGMP code. > > iml->sfmode = MCAST_EXCLUDE; > - rcu_assign_pointer(inet->mc_list, iml); > + RCU_INIT_POINTER(inet->mc_list, iml); > > Obviously iml is not NULL here. > > Please Paul dont Ack a patch only reading the Changelog. Sigh. That will teach me to trust coccinelle. :-( > I'll make a patch to revert all non NULL uses. Please accept my apologies. I will avoid trusting coccinelle quite so much in the future, and thank you for fixing this up. Thanx, Paul