Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756913AbZGHVpZ (ORCPT ); Wed, 8 Jul 2009 17:45:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754761AbZGHVpL (ORCPT ); Wed, 8 Jul 2009 17:45:11 -0400 Received: from mail-fx0-f218.google.com ([209.85.220.218]:47101 "EHLO mail-fx0-f218.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754507AbZGHVpJ (ORCPT ); Wed, 8 Jul 2009 17:45:09 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type:content-transfer-encoding; b=VeRnPZZtNaVXEPQ7uG2w/rdi6Cdxd0n2fetLBLgDbUEkYa1iupMm5tGANZFkKxdlnX nHXlI5q7V5WDsxt30YDEta0r32ev9Ffz+Y2g1sNbgi9f3CVh2bwwxtOpBkEQOvzeMEo6 vSTqHR24yWX3gByBwEFx+zaKed/KZVZjOFvsM= MIME-Version: 1.0 In-Reply-To: <20090708091344.GD3148@ami.dom.local> References: <200907031326.21822.andres@anarazel.de> <200907071811.27570.andres@anarazel.de> <20090708080852.GC3148@ami.dom.local> <200907081029.34527.andres@anarazel.de> <20090708091344.GD3148@ami.dom.local> From: Joao Correia Date: Wed, 8 Jul 2009 22:44:47 +0100 Message-ID: Subject: Re: Soft-Lockup/Race in networking in 2.6.31-rc1+195 ( possibly?caused by netem) To: Jarek Poplawski Cc: Andres Freund , Arun R Bharadwaj , Thomas Gleixner , Stephen Hemminger , netdev@vger.kernel.org, LKML Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2643 Lines: 78 Hello again On Tue, Jul 7, 2009 at 11:47 AM, Andres Freund wrote: > On Tuesday 07 July 2009 12:40:16 Joao Correia wrote: >> I am now running 2.6.31-rc2 for a couple of hours, no freeze. >> >> Let me know what/if i can help with tracking down the original source >> of the problem. > You dont see the problem anymore with the `echo 0 > > /proc/sys/kernel/timer_migration` change (or equivalently with the patch from > Jarek) or has the problem vanished completely? > > Andres > > On Tuesday 07 July 2009 13:03:50 Joao Correia wrote: >> I dont see the problem with the patch from Jarek I have to correct this information. I had inserted `echo 0 >> /proc/sys/kernel/timer_migration` into rc.local, and i left it there when i applied your first patch. Im talking about this patch: diff --git a/kernel/timer.c b/kernel/timer.c index 0b36b9e..011429c 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -634,7 +634,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires, cpu = smp_processor_id(); -#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP) +#if 0 After removing the line from rc.local, and leaving only the patch, the freeze still happens. The patch -does not- prevent the freeze. It was my mistake saying it does, i totally forgot i had added that line to rc.local. So again, the only thing that stops that freeze is `echo 0 >> /proc/sys/kernel/timer_migration`. Apologies for pointing you in the wrong direction. I also tried the other patch provided: kernel/timer.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/kernel/timer.c b/kernel/timer.c index 0b36b9e..61ba855 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -658,6 +658,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires, spin_unlock(&base->lock); base = new_base; spin_lock(&base->lock); + BUG_ON(tbase_get_base(timer->base)); timer_set_base(timer, base); } } but the OPS never triggers, either with your first patch or with the echo 0 > proc[...] I was under the impression that disabling the entry in /proc or applying the first patch would provide the same result, but alas, it does not. Joao Correia [PS Im providing the patches in this email to contextualize this so that people dont get lost] -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/