From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754751AbZBIOfW (ORCPT ); Mon, 9 Feb 2009 09:35:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751898AbZBIOfI (ORCPT ); Mon, 9 Feb 2009 09:35:08 -0500 Received: from mail-bw0-f167.google.com ([209.85.218.167]:45354 "EHLO mail-bw0-f167.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751891AbZBIOfG (ORCPT ); Mon, 9 Feb 2009 09:35:06 -0500 X-Greylist: delayed 2808 seconds by postgrey-1.27 at vger.kernel.org; Mon, 09 Feb 2009 09:35:05 EST DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; b=a66O92kdeFFxm7h+IQUgl9RiX1ypL4NKH5BvrL79p5axXACVh9Yq4BG4K2qtkvp9XQ vcH1MdfWYpViqEDphxnWw5tNTWyGpIQ/EZ/ds5SOFIyYatHwaUOONtPqILu8BHeQCXWv xw2H/ZySTDfbNjidhAKGEa/+JwwAKxql93rm4= MIME-Version: 1.0 In-Reply-To: References: Date: Mon, 9 Feb 2009 16:48:13 +0300 Message-ID: Subject: Re: 2.6.29-rc4: possible circular locking dependency at btrfs_try_spin_lock From: Alexander Beregalov To: linux-btrfs@vger.kernel.org, LKML Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2009/2/9 Alexander Beregalov : > Hi > Is it false positive lockdep warning? > > [ INFO: possible circular locking dependency detected ] > 2.6.29-rc4-00001-gd5b5623 #2 > ------------------------------------------------------- Another one with linux-next [ INFO: possible circular locking dependency detected ] 2.6.29-rc4-next-20090209 #3 ------------------------------------------------------- dbench/31903 is trying to acquire lock: (&eb->lock#2/6){--..}, at: [] btrfs_clear_lock_blocking+0x9d/0xb0 but task is already holding lock: (&eb->lock/7){--..}, at: [] btrfs_clear_lock_blocking+0x9d/0xb0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&eb->lock/7){--..}: [] __lock_acquire+0xe23/0x1290 [] lock_acquire+0x91/0xc0 [] _spin_lock_nested+0x46/0x80 [] btrfs_try_spin_lock+0x8f/0x1a0 [] btrfs_search_slot+0x50e/0xb10 [] btrfs_read_block_groups+0x67/0x390 [] open_ctree+0xe18/0x1120 [] btrfs_get_sb+0x3a8/0x4b0 [] vfs_kern_mount+0x58/0xd0 [] do_kern_mount+0x4e/0x110 [] do_mount+0x291/0x880 [] sys_mount+0xc0/0x100 [] system_call_fastpath+0x16/0x1b [] 0xffffffffffffffff -> #0 (&eb->lock#2/6){--..}: [] __lock_acquire+0xeea/0x1290 [] lock_acquire+0x91/0xc0 [] _spin_lock_nested+0x46/0x80 [] btrfs_clear_lock_blocking+0x9d/0xb0 [] btrfs_clear_path_blocking+0x32/0x50 [] btrfs_search_slot+0x351/0xb10 [] btrfs_insert_empty_items+0xa4/0x4e0 [] __btrfs_alloc_reserved_extent+0xea/0x330 [] btrfs_alloc_extent+0x6e/0xb0 [] btrfs_alloc_free_block+0x5c/0x90 [] __btrfs_cow_block+0x746/0xb00 [] btrfs_cow_block+0x112/0x2d0 [] btrfs_search_slot+0x223/0xb10 [] btrfs_lookup_inode+0x33/0xb0 [] btrfs_update_inode+0x46/0xd0 [] btrfs_dirty_inode+0x45/0x60 [] __mark_inode_dirty+0x35/0x1c0 [] touch_atime+0xd8/0x140 [] vfs_readdir+0xc6/0xd0 [] sys_getdents+0x87/0xe0 [] system_call_fastpath+0x16/0x1b [] 0xffffffffffffffff other info that might help us debug this: 2 locks held by dbench/31903: #0: (&type->i_mutex_dir_key#6){--..}, at: [] vfs_readdir+0x74/0xd0 #1: (&eb->lock/7){--..}, at: [] btrfs_clear_lock_blocking+0x9d/0xb0 stack backtrace: Pid: 31903, comm: dbench Not tainted 2.6.29-rc4-next-20090209 #3 Call Trace: [] print_circular_bug_tail+0x9f/0xf0 [] __lock_acquire+0xeea/0x1290 [] lock_acquire+0x91/0xc0 [] ? btrfs_clear_lock_blocking+0x9d/0xb0 [] ? btrfs_clear_lock_blocking+0x9d/0xb0 [] _spin_lock_nested+0x46/0x80 [] ? btrfs_clear_lock_blocking+0x9d/0xb0 [] btrfs_clear_lock_blocking+0x9d/0xb0 [] btrfs_clear_path_blocking+0x32/0x50 [] btrfs_search_slot+0x351/0xb10 [] ? save_stack_trace+0x2a/0x50 [] ? __btrfs_alloc_reserved_extent+0x60/0x330 [] btrfs_insert_empty_items+0xa4/0x4e0 [] ? trace_hardirqs_on_caller+0x182/0x1e0 [] ? trace_hardirqs_on+0xd/0x10 [] __btrfs_alloc_reserved_extent+0xea/0x330 [] btrfs_alloc_extent+0x6e/0xb0 [] btrfs_alloc_free_block+0x5c/0x90 [] __btrfs_cow_block+0x746/0xb00 [] btrfs_cow_block+0x112/0x2d0 [] btrfs_search_slot+0x223/0xb10 [] ? mark_held_locks+0x56/0xa0 [] ? kmem_cache_alloc+0xb5/0x100 [] btrfs_lookup_inode+0x33/0xb0 [] btrfs_update_inode+0x46/0xd0 [] ? filldir+0x0/0xe0 [] btrfs_dirty_inode+0x45/0x60 [] __mark_inode_dirty+0x35/0x1c0 [] touch_atime+0xd8/0x140 [] vfs_readdir+0xc6/0xd0 [] sys_getdents+0x87/0xe0 [] system_call_fastpath+0x16/0x1b