From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933770Ab3GZVeJ (ORCPT ); Fri, 26 Jul 2013 17:34:09 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:50823 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759945Ab3GZUsk (ORCPT ); Fri, 26 Jul 2013 16:48:40 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ding Tianhong , "David S. Miller" Subject: [ 22/79] ifb: fix rcu_sched self-detected stalls Date: Fri, 26 Jul 2013 13:47:12 -0700 Message-Id: <20130726204724.272198395@linuxfoundation.org> X-Mailer: git-send-email 1.8.3.rc0.20.gb99dd2e In-Reply-To: <20130726204721.849052763@linuxfoundation.org> References: <20130726204721.849052763@linuxfoundation.org> User-Agent: quilt/0.60-5.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: dingtianhong [ Upstream commit 440d57bc5ff55ec1efb3efc9cbe9420b4bbdfefa ] According to the commit 16b0dc29c1af9df341428f4c49ada4f626258082 (dummy: fix rcu_sched self-detected stalls) Eric Dumazet fix the problem in dummy, but the ifb will occur the same problem like the dummy modules. Trying to "modprobe ifb numifbs=30000" triggers : INFO: rcu_sched self-detected stall on CPU After this splat, RTNL is locked and reboot is needed. We must call cond_resched() to avoid this, even holding RTNL. Signed-off-by: Ding Tianhong Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ifb.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/net/ifb.c +++ b/drivers/net/ifb.c @@ -292,8 +292,10 @@ static int __init ifb_init_module(void) rtnl_lock(); err = __rtnl_link_register(&ifb_link_ops); - for (i = 0; i < numifbs && !err; i++) + for (i = 0; i < numifbs && !err; i++) { err = ifb_init_one(i); + cond_resched(); + } if (err) __rtnl_link_unregister(&ifb_link_ops); rtnl_unlock();