Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751059AbaJEFHL (ORCPT ); Sun, 5 Oct 2014 01:07:11 -0400 Received: from mail-qg0-f53.google.com ([209.85.192.53]:41138 "EHLO mail-qg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750801AbaJEFHH (ORCPT ); Sun, 5 Oct 2014 01:07:07 -0400 From: Vince Weaver X-Google-Original-From: Vince Weaver Date: Sun, 5 Oct 2014 01:13:24 -0400 (EDT) To: Mark Rutland cc: linux-kernel@vger.kernel.org, will.deacon@arm.com, Peter Zijlstra , Paul Mackerras , Ingo Molnar , Arnaldo Carvalho de Melo Subject: Re: Perf lockups / stack overflows on v3.17-rc6, x86_64, arm, arm64 In-Reply-To: <20140925152825.GA6531@leverpostej> Message-ID: References: <20140925152825.GA6531@leverpostej> User-Agent: Alpine 2.11 (DEB 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 25 Sep 2014, Mark Rutland wrote: > Log 1, x86_64 lockup > [ 223.007005] [] ? poll_select_copy_remaining+0x130/0x130 > [ 223.007005] [] ? getname_flags+0x4a/0x1a0 > [ 223.007005] [] ? final_putname+0x1d/0x40 > [ 223.007005] [] ? putname+0x24/0x40 > [ 223.007005] [] ? user_path_at_empty+0x5a/0x90 > [ 223.007005] [] ? wake_up_state+0x10/0x10 > [ 223.007005] [] ? eventfd_read+0x38/0x60 > [ 223.007005] [] ? ktime_get_ts64+0x45/0xf0 > [ 223.007005] [] SyS_poll+0x60/0xf0 I have seen issues similar to this before, where the problem appeared to be in poll/hrtimer. Never managed to track down anything useful about the bug. > Log 2, x86_64 stack overflow > [ 346.641345] divide error: 0000 [#1] SMP > [ 346.642010] Modules linked in: > [ 346.642010] CPU: 0 PID: 4076 Comm: perf_fuzzer Not tainted 3.17.0-rc6hark-perf-lockup+ #1 > [ 346.642010] Hardware name: LENOVO 7484A3G/LENOVO, BIOS 5CKT54AUS 09/07/2009 > [ 346.642010] task: ffff8801ac449a70 ti: ffff8801ac574000 task.ti: ffff8801ac574000 > [ 346.642010] RIP: 0010:[] [] find_busiest_group+0x28e/0x8a0 > [ 346.642010] RSP: 0018:ffff8801ac577760 EFLAGS: 00010006 > [ 346.642010] RAX: 00000000000003ff RBX: 0000000000000000 RCX: 00000000ffff8801 > [ 346.642010] RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 > [ 346.642010] RBP: ffff8801ac577890 R08: 0000000000000000 R09: 0000000000000000 > [ 346.704010] ------------[ cut here ]------------ > [ 346.704017] WARNING: CPU: 2 PID: 5 at arch/x86/kernel/irq_64.c:70 handle_irq+0x141/0x150() > [ 346.704019] do_IRQ(): has overflown the kernel stack (cur:1,sp:ffff8801b653fe88,irq stk top-bottom:ffff8801bed00080-ffff8801bed03fc0,exception stk top-bottom:ffff8801bed04080-ffff8801bed0a000) weird, have not seen this before. Though I was hitting a reboot issue that would give really strange crash messages that was possibly fixed by a patch that went into 3.17-rc7. > Log 3, arm64 lockup > ---->8---- > Seeding random number generator with 1411488270 > /proc/sys/kernel/perf_event_max_sample_rate currently: 285518974/s > /proc/sys/kernel/perf_event_paranoid currently: 1142898651 Those last two lines are suspect. Is my fuzzer broken on arm64 somehow? I do try to test on arm occasionally, but my pandaboard suffered massive SD card failure and I haven't had a chance to get it back running yet. I have trouble getting any of my other flock of arm machines running recent upstream kernels. Sorry that I don't have good answers for these bugs, but I will stick them in my perf_fuzzer outstanding bugs list. Vince -- 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/