From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1162081Ab2GLXB5 (ORCPT ); Thu, 12 Jul 2012 19:01:57 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:60450 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1162013Ab2GLWmn (ORCPT ); Thu, 12 Jul 2012 18:42:43 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg KH , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Mark Rustad , Ross Brattain , Nicholas Bellinger Subject: [ 124/187] tcm_fc: Resolve suspicious RCU usage warnings Date: Thu, 12 Jul 2012 15:34:40 -0700 Message-Id: <20120712191533.869731231@linuxfoundation.org> X-Mailer: git-send-email 1.7.10.1.362.g242cab3 In-Reply-To: <20120712191522.742634173@linuxfoundation.org> References: <20120712192421.GA28926@kroah.com> <20120712191522.742634173@linuxfoundation.org> User-Agent: quilt/0.60-20.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Greg KH 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mark Rustad commit 863555be0c81558b1af277addcf68acb8f778860 upstream. Use rcu_dereference_protected to tell rcu that the ft_lport_lock is held during ft_lport_create. This resolved "suspicious RCU usage" warnings when debugging options are turned on. Signed-off-by: Mark Rustad Tested-by: Ross Brattain Signed-off-by: Nicholas Bellinger Signed-off-by: Greg Kroah-Hartman --- drivers/target/tcm_fc/tfc_sess.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/target/tcm_fc/tfc_sess.c +++ b/drivers/target/tcm_fc/tfc_sess.c @@ -58,7 +58,8 @@ static struct ft_tport *ft_tport_create( struct ft_tport *tport; int i; - tport = rcu_dereference(lport->prov[FC_TYPE_FCP]); + tport = rcu_dereference_protected(lport->prov[FC_TYPE_FCP], + lockdep_is_held(&ft_lport_lock)); if (tport && tport->tpg) return tport;