Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758673AbYFPDvR (ORCPT ); Sun, 15 Jun 2008 23:51:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752519AbYFPDvF (ORCPT ); Sun, 15 Jun 2008 23:51:05 -0400 Received: from ug-out-1314.google.com ([66.249.92.171]:60705 "EHLO ug-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752591AbYFPDvD (ORCPT ); Sun, 15 Jun 2008 23:51:03 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=AJNPqH2hwk5HHqfpOW9DknjXEWP3qyzWCbOhgx7382jHmeaLUx+xkrw6KnwGrNC/IW k31gCo53y1nvaZM/j/MDZOTmlxG0xXNJTAZpgZcwUVgF+qIalKhH9IeffXDYvZipAu2s wMG5jJZJyMND4fw3YW9gKix5qEol4SYaICMKs= Date: Mon, 16 Jun 2008 07:46:59 +0400 From: Alexey Dobriyan To: "Paul E. McKenney" 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: <20080616034659.GA7600@martell.zuzino.mipt.ru> References: <20080614181212.GB26421@linux.vnet.ibm.com> <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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080616033126.GF17915@linux.vnet.ibm.com> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2975 Lines: 62 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 -- 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/