From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net ([212.227.17.20]:50187 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932670AbaICRRU (ORCPT ); Wed, 3 Sep 2014 13:17:20 -0400 Received: from [192.168.178.21] ([85.177.149.249]) by mail.gmx.com (mrgmx102) with ESMTPSA (Nemesis) id 0MNf1y-1XVHuv0okk-007GSe for ; Wed, 03 Sep 2014 19:17:19 +0200 Message-ID: <54074D1D.1070509@gmx.de> Date: Wed, 03 Sep 2014 19:17:17 +0200 From: =?UTF-8?B?VG9yYWxmIEbDtnJzdGVy?= MIME-Version: 1.0 To: linux-btrfs@vger.kernel.org Subject: INFO: task btrfs-transacti:2408 blocked for more than 120 seconds. Content-Type: text/plain; charset=utf-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: At a 32 bit stable Gentoo Linux I do have 2 BTRFS file systems : $ mount | grep btrfs /var/lib/portage.fs on /usr/portage type btrfs (rw,noatime,compress=lzo) /var/lib/pkg.fs on /var/db/pkg type btrfs (rw,noatime,compress=lzo) holding a lot of small Gentoo-package-Manager-related files. The first is exported via NMFS so that my KVM can access that tree too. Today I got a hang while upgrading a package at the host and one within the KVM at the same time, syslog tells me: Sep 3 19:10:57 n22 kernel: INFO: task btrfs-transacti:2408 blocked for more than 120 seconds. Sep 3 19:10:57 n22 kernel: Not tainted 3.16.1 #5 Sep 3 19:10:57 n22 kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Sep 3 19:10:57 n22 kernel: btrfs-transacti D 00000000 0 2408 2 0x00000000 Sep 3 19:10:57 n22 kernel: edb15a34 00000086 c10c7efc 00000000 00000001 5197f8f9 00001fa0 c17bf880 Sep 3 19:10:57 n22 kernel: c17bf880 f3630880 f10167c0 c1099ed3 00000002 00000001 00000000 c10c7efc Sep 3 19:10:57 n22 kernel: 118a2543 00000857 ffffffff 00000018 c24d94d3 002180b0 0062c84a abf93cc6 Sep 3 19:10:57 n22 kernel: Call Trace: Sep 3 19:10:57 n22 kernel: [] ? __delayacct_blkio_start+0x1c/0x20 Sep 3 19:10:57 n22 kernel: [] ? ktime_get_ts+0x83/0x180 Sep 3 19:10:57 n22 kernel: [] ? __delayacct_blkio_start+0x1c/0x20 Sep 3 19:10:57 n22 kernel: [] ? wait_on_page_read+0x50/0x50 Sep 3 19:10:57 n22 kernel: [] io_schedule+0x86/0x100 Sep 3 19:10:57 n22 kernel: [] sleep_on_page+0xd/0x20 Sep 3 19:10:57 n22 kernel: [] __wait_on_bit+0x51/0x80 Sep 3 19:10:57 n22 kernel: [] ? wait_on_page_read+0x50/0x50 Sep 3 19:10:57 n22 kernel: [] wait_on_page_bit+0x83/0x90 Sep 3 19:10:57 n22 kernel: [] ? autoremove_wake_function+0x40/0x40 Sep 3 19:10:57 n22 kernel: [] read_extent_buffer_pages+0x2dc/0x2f0 Sep 3 19:10:57 n22 kernel: [] btree_read_extent_buffer_pages.constprop.50+0xc8/0x140 Sep 3 19:10:57 n22 kernel: [] ? free_root_pointers+0x50/0x50 Sep 3 19:10:57 n22 kernel: [] read_tree_block+0x3c/0x60 Sep 3 19:10:57 n22 kernel: [] read_block_for_search.isra.30+0x141/0x390 Sep 3 19:10:57 n22 kernel: [] btrfs_search_slot+0x3a7/0x870 Sep 3 19:10:57 n22 kernel: [] lookup_inline_extent_backref+0x132/0x6e0 Sep 3 19:10:57 n22 kernel: [] ? update_curr+0xeb/0x1a0 Sep 3 19:10:57 n22 kernel: [] ? cpuacct_charge+0x6e/0x90 Sep 3 19:10:57 n22 kernel: [] __btrfs_free_extent+0x13d/0xd10 Sep 3 19:10:57 n22 kernel: [] ? _raw_spin_unlock+0x22/0x30 Sep 3 19:10:57 n22 kernel: [] ? __btrfs_run_delayed_refs+0x117/0x1260 Sep 3 19:10:57 n22 kernel: [] __btrfs_run_delayed_refs+0x8d7/0x1260 Sep 3 19:10:57 n22 kernel: [] ? finish_task_switch+0x79/0x100 Sep 3 19:10:57 n22 kernel: [] ? mutex_unlock+0xd/0x10 Sep 3 19:10:57 n22 kernel: [] btrfs_run_delayed_refs.part.60+0x58/0x220 Sep 3 19:10:57 n22 kernel: [] ? btrfs_run_ordered_operations+0x1b7/0x240 Sep 3 19:10:57 n22 kernel: [] btrfs_run_delayed_refs+0x14/0x30 Sep 3 19:10:57 n22 kernel: [] btrfs_commit_transaction+0x45/0xc70 Sep 3 19:10:57 n22 kernel: [] ? start_transaction+0x7e/0x5b0 Sep 3 19:10:57 n22 kernel: [] transaction_kthread+0x195/0x220 Sep 3 19:10:57 n22 kernel: [] ? btrfs_cleanup_transaction+0x490/0x490 Sep 3 19:10:57 n22 kernel: [] kthread+0xa6/0xc0 Sep 3 19:10:57 n22 kernel: [] ret_from_kernel_thread+0x21/0x30 Sep 3 19:10:57 n22 kernel: [] ? kthread_create_on_node+0x180/0x180 Sep 3 19:10:57 n22 kernel: 2 locks held by btrfs-transacti/2408: Sep 3 19:10:57 n22 kernel: #0: (&fs_info->transaction_kthread_mutex){......}, at: [] transaction_kthread+0x107/0x220 Sep 3 19:10:57 n22 kernel: #1: (&head_ref->mutex){......}, at: [] btrfs_delayed_ref_lock+0x2f/0x1f0 Just FWIW -- Toralf pgp key: 0076 E94E