From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755502Ab0DSPdS (ORCPT ); Mon, 19 Apr 2010 11:33:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:62802 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755444Ab0DSPdQ (ORCPT ); Mon, 19 Apr 2010 11:33:16 -0400 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells To: Trond.Myklebust@netapp.com, paulmck@linux.vnet.ibm.com Cc: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, David Howells Subject: RCU-isms in fs/nfs/delegation.c Date: Mon, 19 Apr 2010 16:33:05 +0100 Message-ID: <14317.1271691185@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I'm trying to redo my NFS RCU warning fixup patch on top of Paul's patches, and I've found a small potential bug: nfs_inode_reclaim_delegation() doesn't use the appropriate accessors/locks to protect NFS_I(inode)->delegation, and nor does it use such to protect *delegation that I can see. It just overwrites the record. Furthermore, for consistency's sake, it should also protect accesses to delegation->cred within that function. Trond: can you confirm that both NFS_I(inode)->delegation and delegation->cred should be considered RCU-protected pointers? David