From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752511Ab1HOSTe (ORCPT ); Mon, 15 Aug 2011 14:19:34 -0400 Received: from smtp-out.google.com ([74.125.121.67]:12726 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751492Ab1HOSTd (ORCPT ); Mon, 15 Aug 2011 14:19:33 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=dkim-signature:date:from:x-x-sender:to:cc:subject: in-reply-to:message-id:references:user-agent:mime-version:content-type:x-system-of-record; b=JU/bIu7Y+XpWXm1Q/L9eISjkNQukAle2IcAG+zIqXuNr0fILZWYp2jECqLi+UZ82+ MgUEfOKRLQUrteR1R7v6Q== Date: Mon, 15 Aug 2011 11:18:46 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@sister.anvils To: Justin Piszcz cc: linux-kernel@vger.kernel.org Subject: Re: kernel 3.0: BUG: soft lockup: find_get_pages+0x51/0x110 In-Reply-To: Message-ID: References: User-Agent: Alpine 2.00 (LSU 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 15 Aug 2011, Justin Piszcz wrote: > Hello, > > What causes this(?) -- am I out of memory(?) or is this a kernel bug? It would be a kernel bug to lock up even if you are out of memory. It does look like you're under memory pressure, but I don't see any OOM. Is this something you've noticed just once, or does it happen repeatedly? Does it always hit somewhere in find_get_pages(), or does the loop span wider than that? I'm answering out of interest in find_get_pages(): which does contain a number of gotos which could result in endless looping; except that they're all supposed to be for very transitory conditions which a second glance at the RCU-protected tree should correct. But if a radix_tree node got corrupted, then yes, it could loop forever. If it's repeatable, please try again with slab poisoning (and frame pointers) enabled? Hugh > > [104147.717815] BUG: soft lockup - CPU#13 stuck for 23s! [kswapd0:934] > [104147.717820] Modules linked in: dm_mod tcp_diag parport_pc ppdev lp > parport inet_diag ub pl2303 ftdi_sio snd_usb_audio snd_pcm_oss snd_mixer_oss > snd_pcm snd_page_alloc snd_hwdep snd_usbmidi_lib snd_seq_dummy snd_seq_oss > snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq snd_timer snd_seq_device > snd soundcore usbserial cdc_acm nouveau serio_raw ttm drm_kms_helper drm > agpgart i2c_algo_bit mxm_wmi wmi i7core_edac edac_core video > [104147.717872] CPU 13 [104147.717874] Modules linked in: dm_mod tcp_diag > parport_pc ppdev lp parport inet_diag ub pl2303 ftdi_sio snd_usb_audio > snd_pcm_oss snd_mixer_oss snd_pcm snd_page_alloc snd_hwdep snd_usbmidi_lib > snd_seq_dummy snd_seq_oss snd_seq_midi snd_rawmidi snd_seq_midi_event > snd_seq snd_timer snd_seq_device snd soundcore usbserial cdc_acm nouveau > serio_raw ttm drm_kms_helper drm agpgart i2c_algo_bit mxm_wmi wmi > i7core_edac edac_core video > [104147.717916] [104147.717921] Pid: 934, comm: kswapd0 Not tainted 3.0.0 #4 > Supermicro X8DTH-i/6/iF/6F/X8DTH > [104147.717928] RIP: 0010:[] [] > find_get_pages+0x51/0x110 > [104147.717940] RSP: 0018:ffff880626127ba0 EFLAGS: 00000246 > [104147.717944] RAX: ffff8800b5e94d10 RBX: ffff880626127b68 RCX: > 000000000000000e > [104147.717948] RDX: 0000000000000003 RSI: 0000000000000000 RDI: > ffffea001b29c8e8 > [104147.717952] RBP: 0000000000000cd7 R08: 0000000000000001 R09: > ffffea001acce040 > [104147.717955] R10: 0000000000000001 R11: ffff8800ad03b930 R12: > ffffffff815b47ce > [104147.717959] R13: ffffea001ec13740 R14: ffff880626127dc0 R15: > ffffffff81087ce4 > [104147.717964] FS: 0000000000000000(0000) GS:ffff88063fce0000(0000) > knlGS:0000000000000000 > [104147.717969] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > [104147.717973] CR2: 000000007ddf2000 CR3: 0000000001843000 CR4: > 00000000000006e0 > [104147.717976] DR0: 0000000000000000 DR1: 0000000000000000 DR2: > 0000000000000000 > [104147.717979] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: > 0000000000000400 > [104147.717983] Process kswapd0 (pid: 934, threadinfo ffff880626126000, task > ffff880626125810) > [104147.717986] Stack: > [104147.717988] 0000000000000001 ffffffff810807fe ffff8800463ed6d8 > ffff880626127c10 > [104147.717998] 00000000000000a9 ffffffffffffffff ffff8800463ed6d8 > ffffea001ec13740 > [104147.718007] 0000000000000002 ffffffff81089e15 0000000000000cd7 > ffffffff8108b905 > [104147.718015] Call Trace: > [104147.718023] [] ? __delete_from_page_cache+0x3e/0xe0 > [104147.718030] [] ? pagevec_lookup+0x15/0x20 > [104147.718036] [] ? invalidate_mapping_pages+0x55/0x130 > [104147.718045] [] ? shrink_icache_memory+0x2c5/0x310 > [104147.718052] [] ? shrink_slab+0x104/0x170 > [104147.718058] [] ? balance_pgdat+0x492/0x600 > [104147.718064] [] ? kswapd+0xac/0x250 > [104147.718071] [] ? abort_exclusive_wait+0xb0/0xb0 > [104147.718077] [] ? balance_pgdat+0x600/0x600 > [104147.718082] [] ? kthread+0x7e/0x90 > [104147.718090] [] ? kernel_thread_helper+0x4/0x10 > [104147.718096] [] ? kthread_worker_fn+0x120/0x120 > [104147.718102] [] ? gs_change+0xb/0xb > [104147.718105] Code: e7 e8 f4 8b 25 00 85 c0 89 c1 0f 84 ba 00 00 00 49 89 > df 31 d2 45 31 f6 66 90 49 8b 07 48 8b 38 48 85 ff 74 3a 40 f6 c7 01 75 57 > <8b> 77 08 85 f6 74 ee 44 8d 46 01 89 f0 4c 8d 4f 08 f0 44 0f b1 > [104147.718149] Call Trace: > [104147.718155] [] ? __delete_from_page_cache+0x3e/0xe0 > [104147.718161] [] ? pagevec_lookup+0x15/0x20 > [104147.718167] [] ? invalidate_mapping_pages+0x55/0x130 > [104147.718174] [] ? shrink_icache_memory+0x2c5/0x310 > [104147.718180] [] ? shrink_slab+0x104/0x170 > [104147.718186] [] ? balance_pgdat+0x492/0x600 > [104147.718193] [] ? kswapd+0xac/0x250 > [104147.718199] [] ? abort_exclusive_wait+0xb0/0xb0 > [104147.718206] [] ? balance_pgdat+0x600/0x600 > [104147.718211] [] ? kthread+0x7e/0x90 > [104147.718217] [] ? kernel_thread_helper+0x4/0x10 > [104147.718224] [] ? kthread_worker_fn+0x120/0x120 > [104147.718229] [] ? gs_change+0xb/0xb > > Justin.