Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932637AbaLBQnZ (ORCPT ); Tue, 2 Dec 2014 11:43:25 -0500 Received: from mail-qc0-f172.google.com ([209.85.216.172]:39341 "EHLO mail-qc0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932236AbaLBQnX (ORCPT ); Tue, 2 Dec 2014 11:43:23 -0500 Message-ID: <547dec29.c71f8c0a.33d1.11d9@mx.google.com> Date: Tue, 2 Dec 2014 14:43:17 -0200 From: =?UTF-8?B?RMOibmllbA==?= Fraga To: "Paul E. McKenney" Cc: Linus Torvalds , Linux Kernel Mailing List Subject: Re: frequent lockups in 3.18rc4 In-Reply-To: <20141201230813.GE25340@linux.vnet.ibm.com> References: <20141126225745.GA30346@redhat.com> <20141127225637.GA24019@redhat.com> <547b8a45.6e608c0a.20f9.1002@mx.google.com> <547bbe36.48548c0a.105c.779c@mx.google.com> <20141201191431.GA17385@linux.vnet.ibm.com> <547ccf74.a5198c0a.25de.26d9@mx.google.com> <20141201230813.GE25340@linux.vnet.ibm.com> Organization: http://www.youtube.com/DanielFragaBR X-Mailer: Claws Mail 3.11.1-9-g1f531c (GTK+ 2.24.25; x86_64-unknown-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 1 Dec 2014 15:08:13 -0800 "Paul E. McKenney" wrote: > Well, this turned out to be way simpler than I expected. Passes > light rcutorture testing. Sometimes you get lucky... Linus, Paul and others, I finally got a call trace with only CONFIG_TREE_PREEMPT_RCU *disabled* using Paul's patch (to trigger it I compiled PHP with make -j8). Dec 2 14:24:39 tux kernel: [ 8475.941616] conftest[9730]: segfault at 0 ip 0000000000400640 sp 00007fffa67ab300 error 4 in conftest[400000+1000] Dec 2 14:24:40 tux kernel: [ 8476.104725] conftest[9753]: segfault at 0 ip 00007f6863024906 sp 00007fff0e31cc48 error 4 in libc-2.19.so[7f6862efe000+1a1000] Dec 2 14:25:54 tux kernel: [ 8550.791697] INFO: rcu_sched detected stalls on CPUs/tasks: { 4} (detected by 0, t=60002 jiffies, g=112854, c=112853, q=0) Dec 2 14:25:54 tux kernel: [ 8550.791702] Task dump for CPU 4: Dec 2 14:25:54 tux kernel: [ 8550.791703] cc1 R running task 0 14344 14340 0x00080008 Dec 2 14:25:54 tux kernel: [ 8550.791706] 000000001bcebcd8 ffff880100000003 ffffffff810cb7f1 ffff88021f5f5c00 Dec 2 14:25:54 tux kernel: [ 8550.791708] ffff88011bcebfd8 ffff88011bcebce8 ffffffff811fb970 ffff8802149a2a00 Dec 2 14:25:54 tux kernel: [ 8550.791710] ffff8802149a2cc8 ffff88011bcebd28 ffffffff8103e979 ffff88020ed01398 Dec 2 14:25:54 tux kernel: [ 8550.791712] Call Trace: Dec 2 14:25:54 tux kernel: [ 8550.791718] [] ? release_pages+0xa1/0x1e0 Dec 2 14:25:54 tux kernel: [ 8550.791722] [] ? cpumask_any_but+0x30/0x40 Dec 2 14:25:54 tux kernel: [ 8550.791725] [] ? flush_tlb_page+0x49/0xf0 Dec 2 14:25:54 tux kernel: [ 8550.791727] [] ? lru_cache_add_active_or_unevictable+0x22/0x90 Dec 2 14:25:54 tux kernel: [ 8550.791731] [] ? alloc_pages_vma+0x72/0x130 Dec 2 14:25:54 tux kernel: [ 8550.791733] [] ? lru_cache_add_active_or_unevictable+0x22/0x90 Dec 2 14:25:54 tux kernel: [ 8550.791735] [] ? handle_mm_fault+0x3a0/0xaf0 Dec 2 14:25:54 tux kernel: [ 8550.791737] [] ? __do_page_fault+0x224/0x4c0 Dec 2 14:25:54 tux kernel: [ 8550.791740] [] ? new_sync_write+0x7c/0xb0 Dec 2 14:25:55 tux kernel: [ 8550.791743] [] ? fsnotify+0x27c/0x350 Dec 2 14:25:55 tux kernel: [ 8550.791746] [] ? rcu_eqs_enter+0x93/0xa0 Dec 2 14:25:55 tux kernel: [ 8550.791748] [] ? rcu_user_enter+0xe/0x10 Dec 2 14:25:55 tux kernel: [ 8550.791749] [] ? do_page_fault+0x5a/0x70 Dec 2 14:25:55 tux kernel: [ 8550.791752] [] ? page_fault+0x22/0x30 If you need more info/testing, just ask. -- Linux 3.17.0-dirty: Shuffling Zombie Juror http://www.youtube.com/DanielFragaBR http://exchangewar.info Bitcoin: 12H6661yoLDUZaYPdah6urZS5WiXwTAUgL -- 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/