Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758490AbYFNKyS (ORCPT ); Sat, 14 Jun 2008 06:54:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753520AbYFNKyH (ORCPT ); Sat, 14 Jun 2008 06:54:07 -0400 Received: from wa-out-1112.google.com ([209.85.146.179]:55691 "EHLO wa-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752392AbYFNKyD (ORCPT ); Sat, 14 Jun 2008 06:54:03 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:mime-version:content-type :content-transfer-encoding:content-disposition; b=UrC9qM8Hnp26GKwScoIOEfZgGReVuNI6JjsldnLWPHMEZg1e9vW5TWPQRbtF7Oe2xv YrdtPur4YwaVhyTbC0afwvpw3It2WEKXQ4AqRPieOdnCpLaBG5VFmx3RfRsH5uRIi9nM mmQmAJdg43kfKWuHuEkD/ywFdY78r0cK8vWhg= Message-ID: <6278d2220806140354i7f163086i6127664d8c2d88a9@mail.gmail.com> Date: Sat, 14 Jun 2008 11:54:02 +0100 From: "Daniel J Blueman" To: "Christoph Lameter" Subject: 2.6.26-rc5: SLUB debug, lockdep warning... Cc: "Linux Kernel" MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4634 Lines: 109 When enabling lockdep + SLUB debugging, I spotted this recursive lock-acquisition warning [1] when booting, however it doesn't always pop out. Let me know if you need further information etc. Daniel --- [1] ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.26-rc5-201c #1 ------------------------------------------------------- nscd/3669 is trying to acquire lock: (&n->list_lock){.+..}, at: [] deactivate_slab+0x173/0x1e0 but task is already holding lock: (&obj_hash[i].lock){++..}, at: [] __debug_object_init+0x2f/0x350 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&obj_hash[i].lock){++..}: [] __lock_acquire+0xbdd/0x1020 [] lock_acquire+0x65/0x90 [] _spin_lock_irqsave+0x47/0x80 [] __debug_check_no_obj_freed+0x6c/0x160 [] debug_check_no_obj_freed+0x15/0x20 [] free_hot_cold_page+0x10d/0x250 [] free_hot_page+0xb/0x10 [] __free_pages+0x25/0x40 [] __free_slab+0x96/0x150 [] discard_slab+0x2f/0x50 [] kmem_cache_shrink+0x150/0x280 [] acpi_os_purge_cache+0x9/0xd [] acpi_purge_cached_objects+0x10/0x38 [] acpi_initialize_objects+0x49/0x54 [] acpi_init+0x8c/0x221 [] kernel_init+0x138/0x320 [] child_rip+0xa/0x12 [] 0xffffffffffffffff -> #0 (&n->list_lock){.+..}: [] __lock_acquire+0xa47/0x1020 [] lock_acquire+0x65/0x90 [] _spin_lock+0x31/0x60 [] deactivate_slab+0x173/0x1e0 [] __slab_alloc+0x132/0x550 [] kmem_cache_alloc+0xc0/0xd0 [] __debug_object_init+0x2b4/0x350 [] debug_object_init_on_stack+0x1c/0x30 [] hrtimer_init_on_stack+0x29/0x50 [] futex_wait+0x249/0x480 [] do_futex+0xb8/0xad0 [] sys_futex+0xa5/0x120 [] system_call_after_swapgs+0x7b/0x80 [] 0xffffffffffffffff other info that might help us debug this: 1 lock held by nscd/3669: #0: (&obj_hash[i].lock){++..}, at: [] __debug_object_init+0x2f/0x350 stack backtrace: Pid: 3669, comm: nscd Not tainted 2.6.26-rc5-201c #1 Call Trace: [] print_circular_bug_tail+0x83/0x90 [] __lock_acquire+0xa47/0x1020 [] lock_acquire+0x65/0x90 [] ? deactivate_slab+0x173/0x1e0 [] _spin_lock+0x31/0x60 [] deactivate_slab+0x173/0x1e0 [] __slab_alloc+0x132/0x550 [] ? __debug_object_init+0x2b4/0x350 [] ? __debug_object_init+0x2b4/0x350 [] kmem_cache_alloc+0xc0/0xd0 [] __debug_object_init+0x2b4/0x350 [] debug_object_init_on_stack+0x1c/0x30 [] hrtimer_init_on_stack+0x29/0x50 [] futex_wait+0x249/0x480 [] ? get_lock_stats+0x23/0x70 [] ? flat_send_IPI_mask+0x55/0x90 [] ? native_smp_send_reschedule+0x2e/0x50 [] ? __resched_task+0x6b/0x80 [] ? hrtick_start_fair+0x11c/0x160 [] ? default_wake_function+0x0/0x10 [] do_futex+0xb8/0xad0 [] ? get_lock_stats+0x23/0x70 [] ? lock_release_holdtime+0x66/0x80 [] ? __up_read+0x4d/0xb0 [] ? _spin_unlock_irqrestore+0x65/0x80 [] ? trace_hardirqs_on+0xbf/0x150 [] ? read_tsc+0x9/0x20 [] ? getnstimeofday+0x36/0xb0 [] ? ktime_get_ts+0x4a/0x60 [] sys_futex+0xa5/0x120 [] system_call_after_swapgs+0x7b/0x80 -- Daniel J Blueman -- 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/