From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753707AbZGNOVs (ORCPT ); Tue, 14 Jul 2009 10:21:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752406AbZGNOVr (ORCPT ); Tue, 14 Jul 2009 10:21:47 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:49131 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751372AbZGNOVr (ORCPT ); Tue, 14 Jul 2009 10:21:47 -0400 Subject: xfs mr_lock vs mmap_sem lock inversion? From: Peter Zijlstra To: Christoph Hellwig Cc: linux-kernel Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Tue, 14 Jul 2009 16:15:55 +0200 Message-Id: <1247580955.7500.97.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.26.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, I seem to be getting lots (as in one every boot) of these: [ 84.692079] ======================================================= [ 84.692082] [ INFO: possible circular locking dependency detected ] [ 84.692084] 2.6.31-rc2-tip #179 [ 84.692086] ------------------------------------------------------- [ 84.692088] plasma/7446 is trying to acquire lock: [ 84.692090] (&mm->mmap_sem){++++++}, at: [] do_page_fault+0x179/0x2a1 [ 84.692098] [ 84.692098] but task is already holding lock: [ 84.692100] (&(&ip->i_iolock)->mr_lock){++++++}, at: [] xfs_ilock+0x49/0x7e [xfs] [ 84.692126] [ 84.692127] which lock already depends on the new lock. [ 84.692127] [ 84.692129] [ 84.692129] the existing dependency chain (in reverse order) is: [ 84.692131] [ 84.692131] -> #1 (&(&ip->i_iolock)->mr_lock){++++++}: [ 84.692135] [] __lock_acquire+0xa62/0xbea [ 84.692140] [] lock_acquire+0xfc/0x128 [ 84.692143] [] down_write_nested+0x2f/0x3b [ 84.692147] [] xfs_ilock+0x2c/0x7e [xfs] [ 84.692166] [] xfs_free_eofblocks+0x11c/0x20a [xfs] [ 84.692184] [] xfs_release+0x138/0x145 [xfs] [ 84.692203] [] xfs_file_release+0x15/0x19 [xfs] [ 84.692221] [] __fput+0xfb/0x1a6 [ 84.692225] [] fput+0x1d/0x1f [ 84.692228] [] remove_vma+0x3b/0x71 [ 84.692232] [] do_munmap+0x309/0x32b [ 84.692235] [] sys_munmap+0x45/0x5e [ 84.692238] [] sysenter_dispatch+0x7/0x33 [ 84.692242] [] 0xffffffffffffffff [ 84.692260] [ 84.692260] -> #0 (&mm->mmap_sem){++++++}: [ 84.692263] [] __lock_acquire+0x956/0xbea [ 84.692267] [] lock_acquire+0xfc/0x128 [ 84.692270] [] down_read+0x34/0x40 [ 84.692273] [] do_page_fault+0x179/0x2a1 [ 84.692276] [] page_fault+0x25/0x30 [ 84.692280] [] generic_file_aio_read+0x364/0x5ba [ 84.692284] [] xfs_read+0x18d/0x1fa [xfs] [ 84.692302] [] xfs_file_aio_read+0x64/0x67 [xfs] [ 84.692320] [] do_sync_read+0xec/0x132 [ 84.692324] [] vfs_read+0xad/0x107 [ 84.692327] [] sys_read+0x4c/0x75 [ 84.692330] [] sysenter_dispatch+0x7/0x33 [ 84.692333] [] 0xffffffffffffffff [ 84.692337] [ 84.692338] other info that might help us debug this: [ 84.692338] [ 84.692340] 1 lock held by plasma/7446: [ 84.692342] #0: (&(&ip->i_iolock)->mr_lock){++++++}, at: [] xfs_ilock+0x49/0x7e [xfs] [ 84.692363] [ 84.692364] stack backtrace: [ 84.692366] Pid: 7446, comm: plasma Not tainted 2.6.31-rc2-tip #179 [ 84.692368] Call Trace: [ 84.692372] [] print_circular_bug_tail+0x71/0x7c [ 84.692375] [] __lock_acquire+0x956/0xbea [ 84.692379] [] lock_acquire+0xfc/0x128 [ 84.692382] [] ? do_page_fault+0x179/0x2a1 [ 84.692385] [] down_read+0x34/0x40 [ 84.692388] [] ? do_page_fault+0x179/0x2a1 [ 84.692391] [] do_page_fault+0x179/0x2a1 [ 84.692394] [] page_fault+0x25/0x30 [ 84.692398] [] ? file_read_actor+0x3c/0x132 [ 84.692401] [] ? __rcu_read_unlock+0x45/0x50 [ 84.692404] [] generic_file_aio_read+0x364/0x5ba [ 84.692424] [] ? xfs_ilock+0x49/0x7e [xfs] [ 84.692442] [] xfs_read+0x18d/0x1fa [xfs] [ 84.692461] [] xfs_file_aio_read+0x64/0x67 [xfs] [ 84.692465] [] do_sync_read+0xec/0x132 [ 84.692468] [] ? autoremove_wake_function+0x0/0x3d [ 84.692471] [] ? __rcu_read_lock+0x0/0x3f [ 84.692476] [] ? security_file_permission+0x16/0x18 [ 84.692479] [] vfs_read+0xad/0x107 [ 84.692482] [] sys_read+0x4c/0x75 [ 84.692485] [] sysenter_dispatch+0x7/0x33 [ 84.692489] [] ? trace_hardirqs_on_thunk+0x3a/0x3f