From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752281Ab1GGTrV (ORCPT ); Thu, 7 Jul 2011 15:47:21 -0400 Received: from mail-ww0-f44.google.com ([74.125.82.44]:36090 "EHLO mail-ww0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751391Ab1GGTrU (ORCPT ); Thu, 7 Jul 2011 15:47:20 -0400 From: julie Sullivan To: paulmck@linux.vnet.ibm.com Subject: Re: PROBLEM: 3.0-rc kernels unbootable since -rc3 Date: Thu, 7 Jul 2011 20:47:13 +0100 User-Agent: KMail/1.13.6 (Linux/3.0.0-rc4-revert+; KDE/4.6.2; x86_64; ; ) Cc: julie Sullivan , linux-kernel@vger.kernel.org, mingo@elte.hu, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@polymtl.ca, josh@joshtriplett.org, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, Valdis.Kletnieks@vt.edu, dhowells@redhat.com, eric.dumazet@gmail.com, darren@dvhart.com, patches@linaro.org, torvalds@linux-foundation.org References: <20110706212348.GO6014@linux.vnet.ibm.com> In-Reply-To: <20110706212348.GO6014@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201107072047.14429.kernelmail.jms@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 06 July 2011 22:23:48 Paul E. McKenney wrote: > On Wed, Jul 06, 2011 at 10:10:16PM +0100, julie Sullivan wrote: > > None of my kernels after 3.0-rc3 will boot on my Dell XPS-M1730 > > (x86-64 2-core) test box running > > Ubuntu (Kubuntu) 11.04 (i.e. the first unbootable one was -rc4). > > The machine freezes immediately after selecting the kernel from the > > bootloader menu, leaving > > me with a blank blue screen so I can't give you any log messages. > > > > It bisects to the following commit: > > > > commit a46e0899eec7a3069bcadd45dfba7bf67c6ed016 > > Author: Paul E. McKenney > > Date: Wed Jun 15 15:47:09 2011 -0700 > > > > rcu: use softirq instead of kthreads except when RCU_BOOST=y > > > > This patch #ifdefs RCU kthreads out of the kernel unless RCU_BOOST=y, > > thus eliminating context-switch overhead if RCU priority boosting has > > not been configured. > > > > Signed-off-by: Paul E. McKenney > > Hello, Julie, > > One approach would be to cherry-pick the following commits: > > f8b7fc6b514f34a51875dd48dff70d4d17a54f38 rcu: Move RCU_BOOST #ifdefs to header f > a46e0899eec7a3069bcadd45dfba7bf67c6ed016 rcu: use softirq instead of kthreads ex > 09223371deac67d08ca0b70bd18787920284c967 rcu: Use softirq to address performance > 9a432736904d386cda28b987b38ba14dae960ecc rcu: Simplify curing of load woes > > Another approach would be to move ahead to v3.0-rc4 or later. > > Thanx, Paul Hi Paul Thanks for your prompt reply, sorry for the delay in mine (real life intervened :-) I tried reverting those 4 commits on v3.0-rc4 and can confirm that it _does_ give me a bootable 3.0-rc4 kernel. I'll do some more testing. If you would like me to try anything specific just let me know :-) Cheers Julie