Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755350AbZKMJGa (ORCPT ); Fri, 13 Nov 2009 04:06:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755070AbZKMJGZ (ORCPT ); Fri, 13 Nov 2009 04:06:25 -0500 Received: from bombadil.infradead.org ([18.85.46.34]:35978 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755007AbZKMJGV (ORCPT ); Fri, 13 Nov 2009 04:06:21 -0500 Subject: Re: -next: Nov 12 - kernel BUG at kernel/sched.c:7359! From: Peter Zijlstra To: Sachin Sant Cc: LKML , Stephen Rothwell , linux-next@vger.kernel.org, Ingo Molnar , Mike Galbraith , Gautham R Shenoy In-Reply-To: <4AFD2027.5060303@in.ibm.com> References: <20091112195101.63263490.sfr@canb.auug.org.au> <4AFBF73B.5040500@in.ibm.com> <1258027820.4039.129.camel@laptop> <4AFBFE3D.80507@in.ibm.com> <1258028831.4039.152.camel@laptop> <1258045831.4039.736.camel@laptop> <4AFD2027.5060303@in.ibm.com> Content-Type: text/plain; charset="UTF-8" Date: Fri, 13 Nov 2009 10:06:13 +0100 Message-ID: <1258103173.4039.1070.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1362 Lines: 38 On Fri, 2009-11-13 at 14:30 +0530, Sachin Sant wrote: > Peter Zijlstra wrote: > > So what we need to do is make the whole of select_task_rq_fair() > > cpu_online/active_mask aware, or give up and simply punt: > > > > diff --git a/kernel/sched.c b/kernel/sched.c > > index 1f2e99d..62df61c 100644 > > --- a/kernel/sched.c > > +++ b/kernel/sched.c > > @@ -2377,6 +2377,9 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, > > task_rq_unlock(rq, &flags); > > > > cpu = p->sched_class->select_task_rq(p, SD_BALANCE_WAKE, wake_flags); > > + if (!cpu_active(cpu)) > > + cpu = cpumask_any_and(&p->cpus_allowed, cpu_active_mask); > > + > > if (cpu != orig_cpu) { > > local_irq_save(flags); > > rq = cpu_rq(cpu); > > > > > > Something I think Mike also tried and didn't deadlock for him.. > > > > Sachin, Mike, could you try the above snippet and verify if it does > > indeed solve your respective issues? > > > Unfortunately the above patch made things worse. With this patch > the machine failed to boot with following oops Ugh, more head scratching for me then.. Thanks for testing. -- 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/