From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754864Ab0FOW3v (ORCPT ); Tue, 15 Jun 2010 18:29:51 -0400 Received: from e5.ny.us.ibm.com ([32.97.182.145]:46134 "EHLO e5.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753345Ab0FOW3t (ORCPT ); Tue, 15 Jun 2010 18:29:49 -0400 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@elte.hu, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@polymtl.ca, josh@joshtriplett.org, dvhltc@us.ibm.com, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, Valdis.Kletnieks@vt.edu, dhowells@redhat.com, eric.dumazet@gmail.com, "Paul E. McKenney" Subject: [PATCH tip/core/urgent 3/3] idr: fix RCU lockdep splat in idr_get_next() Date: Tue, 15 Jun 2010 15:29:43 -0700 Message-Id: <1276640983-14641-3-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.0.6 In-Reply-To: <20100615222923.GA14571@linux.vnet.ibm.com> References: <20100615222923.GA14571@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Convert to rcu_dereference_raw() given that many callers may have many different locking models. Located-by: Miles Lane Tested-by: Miles Lane Signed-off-by: Paul E. McKenney --- lib/idr.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/lib/idr.c b/lib/idr.c index c1a2069..7f1a4f0 100644 --- a/lib/idr.c +++ b/lib/idr.c @@ -602,7 +602,7 @@ void *idr_get_next(struct idr *idp, int *nextidp) /* find first ent */ n = idp->layers * IDR_BITS; max = 1 << n; - p = rcu_dereference(idp->top); + p = rcu_dereference_raw(idp->top); if (!p) return NULL; @@ -610,7 +610,7 @@ void *idr_get_next(struct idr *idp, int *nextidp) while (n > 0 && p) { n -= IDR_BITS; *paa++ = p; - p = rcu_dereference(p->ary[(id >> n) & IDR_MASK]); + p = rcu_dereference_raw(p->ary[(id >> n) & IDR_MASK]); } if (p) { -- 1.7.0.6