Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755379AbYFQDmu (ORCPT ); Mon, 16 Jun 2008 23:42:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753734AbYFQDmm (ORCPT ); Mon, 16 Jun 2008 23:42:42 -0400 Received: from E23SMTP04.au.ibm.com ([202.81.18.173]:35731 "EHLO e23smtp04.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753642AbYFQDml (ORCPT ); Mon, 16 Jun 2008 23:42:41 -0400 Date: Mon, 16 Jun 2008 20:42:28 -0700 From: "Paul E. McKenney" To: Alexey Dobriyan Cc: Linus Torvalds , Oleg Nesterov , Adrian Bunk , "Rafael J. Wysocki" , Linux Kernel Mailing List Subject: Re: [Bug #10815] 2.6.26-rc4: RIP find_pid_ns+0x6b/0xa0 Message-ID: <20080617034228.GA18217@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <20080614194338.GA4820@martell.zuzino.mipt.ru> <20080615033001.GE26421@linux.vnet.ibm.com> <20080615162150.GA8289@martell.zuzino.mipt.ru> <20080615181710.GA17915@linux.vnet.ibm.com> <20080615232754.GD17915@linux.vnet.ibm.com> <20080616030154.GA7445@martell.zuzino.mipt.ru> <20080616033126.GF17915@linux.vnet.ibm.com> <20080616034659.GA7600@martell.zuzino.mipt.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080616034659.GA7600@martell.zuzino.mipt.ru> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3228 Lines: 66 On Mon, Jun 16, 2008 at 07:46:59AM +0400, Alexey Dobriyan wrote: > On Sun, Jun 15, 2008 at 08:31:26PM -0700, Paul E. McKenney wrote: > > On Mon, Jun 16, 2008 at 07:01:54AM +0400, Alexey Dobriyan wrote: > > > On Sun, Jun 15, 2008 at 04:38:24PM -0700, Linus Torvalds wrote: > > > > On Sun, 15 Jun 2008, Paul E. McKenney wrote: > > > > > > > > > > If that is the right thing to do. I would feel better about it if I > > > > > could reproduce the failure. > > > > > > > > Is there some configuration thing that might make it happen for Alexey but > > > > not for you? The only obvious one is the normal PREEMPT thing, but > > > > PREEMPT_RCU obviously depends on that, so there must be something else. > > > > > > > > CONFIG_SMP? CONFIG_NO_HZ? CONFIG_[RT|FAIR]_GROUP_SCHED? There's a number > > > > of config options that change scheduling details.. > > > > > > The only way I can "fix" rcutorture here is SMP=n (not maxcpus=1!). > > > > I am running SMP=y without seeing the problem. > > > > > Among things tried and do not matter are NO_HZ, HIGH_RES_TIMERS, turning off > > > debugging options (one by one and in bulk), DEBUG_PER_CPU_MAPS, HZ tweaks, > > > SCHED_MC. > > > > > > All of this doesn't help, but SMP=n does. > > > > Attached is the compressed config file I used for a run on a POWER > > machine. I have used similar config files for x86. For this run, I built > > LTP, installed it, started rcutorture, ran LTP, then ended rcutorture. > > > > The only other thing I can think of is that Alexey's machines are > > somehow managing to nest NMIs or something. I can produce a fix for > > that, but have no way of testing it. > > No NMIs here according to /proc/interrupts . > > CPU0 CPU1 > 0: 42 0 IO-APIC-edge timer > 1: 8 0 IO-APIC-edge i8042 > 8: 1 0 IO-APIC-edge rtc > 9: 0 0 IO-APIC-fasteoi acpi > 16: 0 0 IO-APIC-fasteoi ahci, uhci_hcd:usb1 > 17: 35 0 IO-APIC-fasteoi pata_jmicron, uhci_hcd:usb2 > 18: 0 0 IO-APIC-fasteoi ehci_hcd:usb3, uhci_hcd:usb6 > 19: 6238 0 IO-APIC-fasteoi ata_piix, ata_piix, uhci_hcd:usb5 > 22: 278 0 IO-APIC-fasteoi HDA Intel > 23: 2802 0 IO-APIC-fasteoi uhci_hcd:usb4, ehci_hcd:usb7, eth1 > 319: 5126 0 PCI-MSI-edge eth0 > NMI: 0 0 Non-maskable interrupts > LOC: 66777 66036 Local timer interrupts > RES: 3031 3403 Rescheduling interrupts > CAL: 17 62 function call interrupts > TLB: 671 900 TLB shootdowns > TRM: 0 0 Thermal event interrupts > THR: 0 0 Threshold APIC interrupts > SPU: 0 0 Spurious interrupts > ERR: 0 OK, thank you for the information. Looking elsewhere... Thanx, Paul -- 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/