From: Ben Greear <greearb@candelatech.com>
To: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: lockdep splat in 3.0-rc7 (circular locking, scheduler related?)
Date: Tue, 12 Jul 2011 13:51:23 -0700 [thread overview]
Message-ID: <4E1CB3CB.5070108@candelatech.com> (raw)
Been seeing this one for a while in 3.0, and still in -rc7.
Kernel has lots of debug enabled, and some nfs patches.
=======================================================
[ INFO: possible circular locking dependency detected ]
3.0.0-rc7+ #23
-------------------------------------------------------
ip/30705 is trying to acquire lock:
(rcu_node_level_0){..-...}, at: [<ffffffff810a7455>] rcu_report_unblock_qs_rnp+0x52/0x72
but task is already holding lock:
(&rq->lock){-.-.-.}, at: [<ffffffff81045d88>] sched_ttwu_pending+0x34/0x58
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (&rq->lock){-.-.-.}:
[<ffffffff8107b4e5>] lock_acquire+0xf4/0x14b
[<ffffffff8147e6d1>] _raw_spin_lock+0x36/0x45
[<ffffffff8103d9fe>] __task_rq_lock+0x5b/0x89
[<ffffffff81046a99>] wake_up_new_task+0x41/0x116
[<ffffffff810496b9>] do_fork+0x207/0x2f1
[<ffffffff81010d25>] kernel_thread+0x70/0x72
[<ffffffff81465c0d>] rest_init+0x21/0xd7
[<ffffffff81aa9c76>] start_kernel+0x3bd/0x3c8
[<ffffffff81aa92cd>] x86_64_start_reservations+0xb8/0xbc
[<ffffffff81aa93d2>] x86_64_start_kernel+0x101/0x110
-> #2 (&p->pi_lock){-.-.-.}:
[<ffffffff8107b4e5>] lock_acquire+0xf4/0x14b
[<ffffffff8147e7e5>] _raw_spin_lock_irqsave+0x4e/0x60
[<ffffffff810468b3>] try_to_wake_up+0x29/0x1a0
[<ffffffff81046a37>] default_wake_function+0xd/0xf
[<ffffffff810674fe>] autoremove_wake_function+0x13/0x38
[<ffffffff810395d0>] __wake_up_common+0x49/0x7f
[<ffffffff8103c78a>] __wake_up+0x34/0x48
[<ffffffff810a74c5>] rcu_report_exp_rnp+0x50/0x89
[<ffffffff810a804e>] __rcu_read_unlock+0x1e9/0x24e
[<ffffffff81110c01>] rcu_read_unlock+0x21/0x23
[<ffffffff81113320>] __mem_cgroup_try_charge+0x195/0x4f5
[<ffffffff81114c8c>] mem_cgroup_charge_common+0xa7/0xdb
[<ffffffff81114e22>] mem_cgroup_newpage_charge+0x34/0x43
[<ffffffff810ea0cb>] handle_pte_fault+0x1b6/0x84d
[<ffffffff810ea90e>] handle_mm_fault+0x1ac/0x1c4
[<ffffffff81481e34>] do_page_fault+0x32d/0x374
[<ffffffff8147f605>] page_fault+0x25/0x30
-> #1 (sync_rcu_preempt_exp_wq.lock){......}:
[<ffffffff8107b4e5>] lock_acquire+0xf4/0x14b
[<ffffffff8147e7e5>] _raw_spin_lock_irqsave+0x4e/0x60
[<ffffffff8103c773>] __wake_up+0x1d/0x48
[<ffffffff810a74c5>] rcu_report_exp_rnp+0x50/0x89
[<ffffffff810a8c48>] sync_rcu_preempt_exp_init.clone.0+0x3e/0x53
[<ffffffff810a8d38>] synchronize_rcu_expedited+0xdb/0x1c3
[<ffffffff813c0fd3>] synchronize_net+0x25/0x2e
[<ffffffff813c35a2>] rollback_registered_many+0xee/0x1e1
[<ffffffff813c36a9>] unregister_netdevice_many+0x14/0x55
[<ffffffffa036a138>] 0xffffffffa036a138
[<ffffffff813bdb5d>] ops_exit_list+0x25/0x4e
[<ffffffff813bdda9>] unregister_pernet_operations+0x5c/0x8e
[<ffffffff813bde42>] unregister_pernet_subsys+0x22/0x32
[<ffffffffa0372e2c>] 0xffffffffa0372e2c
[<ffffffff81083d56>] sys_delete_module+0x1aa/0x20e
[<ffffffff81484fd2>] system_call_fastpath+0x16/0x1b
-> #0 (rcu_node_level_0){..-...}:
[<ffffffff8107acf2>] __lock_acquire+0xae6/0xdd5
[<ffffffff8107b4e5>] lock_acquire+0xf4/0x14b
[<ffffffff8147e6d1>] _raw_spin_lock+0x36/0x45
[<ffffffff810a7455>] rcu_report_unblock_qs_rnp+0x52/0x72
[<ffffffff810a800c>] __rcu_read_unlock+0x1a7/0x24e
[<ffffffff8103d33d>] rcu_read_unlock+0x21/0x23
[<ffffffff8103d392>] cpuacct_charge+0x53/0x5b
[<ffffffff81044cea>] update_curr+0x11f/0x15a
[<ffffffff81045a1a>] enqueue_task_fair+0x46/0x22a
[<ffffffff8103d2b0>] enqueue_task+0x61/0x68
[<ffffffff8103d2df>] activate_task+0x28/0x30
[<ffffffff81040b26>] ttwu_activate+0x12/0x34
[<ffffffff81045d42>] ttwu_do_activate.clone.4+0x2d/0x3f
[<ffffffff81045d97>] sched_ttwu_pending+0x43/0x58
[<ffffffff81045db5>] scheduler_ipi+0x9/0xb
[<ffffffff81021e40>] smp_reschedule_interrupt+0x25/0x27
[<ffffffff81485ef3>] reschedule_interrupt+0x13/0x20
[<ffffffff810c98dc>] rcu_read_unlock+0x21/0x23
[<ffffffff810c999f>] find_get_pages_tag+0xc1/0xed
[<ffffffff810d3480>] pagevec_lookup_tag+0x20/0x29
[<ffffffff811979e7>] write_cache_pages_da+0xeb/0x37b
[<ffffffff81197f65>] ext4_da_writepages+0x2ee/0x565
[<ffffffff810d2ccf>] do_writepages+0x1f/0x28
[<ffffffff810ca39c>] __filemap_fdatawrite_range+0x4e/0x50
[<ffffffff810ca8a6>] filemap_flush+0x17/0x19
[<ffffffff81193447>] ext4_alloc_da_blocks+0x81/0xab
[<ffffffff8118d669>] ext4_release_file+0x35/0xb3
[<ffffffff8111b07c>] fput+0x117/0x1b2
[<ffffffff81117b56>] filp_close+0x6d/0x78
[<ffffffff8104c2f7>] put_files_struct+0xca/0x190
[<ffffffff8104c403>] exit_files+0x46/0x4e
[<ffffffff8104deb7>] do_exit+0x2b5/0x760
[<ffffffff8104e3e0>] do_group_exit+0x7e/0xa9
[<ffffffff8104e41d>] sys_exit_group+0x12/0x16
[<ffffffff81484fd2>] system_call_fastpath+0x16/0x1b
other info that might help us debug this:
Chain exists of:
rcu_node_level_0 --> &p->pi_lock --> &rq->lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&rq->lock);
lock(&p->pi_lock);
lock(&rq->lock);
lock(rcu_node_level_0);
*** DEADLOCK ***
2 locks held by ip/30705:
#0: (jbd2_handle){+.+...}, at: [<ffffffff811c9e68>] start_this_handle+0x605/0x64d
#1: (&rq->lock){-.-.-.}, at: [<ffffffff81045d88>] sched_ttwu_pending+0x34/0x58
stack backtrace:
Pid: 30705, comm: ip Not tainted 3.0.0-rc7+ #23
Call Trace:
<IRQ> [<ffffffff8147ed33>] ? _raw_spin_unlock_irqrestore+0x6b/0x79
[<ffffffff8107a14d>] print_circular_bug+0x1fe/0x20f
[<ffffffff8107acf2>] __lock_acquire+0xae6/0xdd5
[<ffffffff810a7455>] ? rcu_report_unblock_qs_rnp+0x52/0x72
[<ffffffff8107b4e5>] lock_acquire+0xf4/0x14b
[<ffffffff810a7455>] ? rcu_report_unblock_qs_rnp+0x52/0x72
[<ffffffff8147e6d1>] _raw_spin_lock+0x36/0x45
[<ffffffff810a7455>] ? rcu_report_unblock_qs_rnp+0x52/0x72
[<ffffffff8147ecbb>] ? _raw_spin_unlock+0x45/0x52
[<ffffffff810a7455>] rcu_report_unblock_qs_rnp+0x52/0x72
[<ffffffff810a7f41>] ? __rcu_read_unlock+0xdc/0x24e
[<ffffffff810a800c>] __rcu_read_unlock+0x1a7/0x24e
[<ffffffff8103d33d>] rcu_read_unlock+0x21/0x23
[<ffffffff8103d392>] cpuacct_charge+0x53/0x5b
[<ffffffff81044cea>] update_curr+0x11f/0x15a
[<ffffffff81045a1a>] enqueue_task_fair+0x46/0x22a
[<ffffffff8103d2b0>] enqueue_task+0x61/0x68
[<ffffffff8103d2df>] activate_task+0x28/0x30
[<ffffffff81040b26>] ttwu_activate+0x12/0x34
[<ffffffff81045d42>] ttwu_do_activate.clone.4+0x2d/0x3f
[<ffffffff81045d97>] sched_ttwu_pending+0x43/0x58
[<ffffffff81045db5>] scheduler_ipi+0x9/0xb
[<ffffffff81021e40>] smp_reschedule_interrupt+0x25/0x27
[<ffffffff81485ef3>] reschedule_interrupt+0x13/0x20
<EOI> [<ffffffff8122d6ce>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[<ffffffff810a7eb8>] ? __rcu_read_unlock+0x53/0x24e
[<ffffffff810c98bb>] ? radix_tree_deref_slot+0x57/0x57
[<ffffffff8107b20e>] ? lock_release+0x6/0x1e9
[<ffffffff810c98dc>] rcu_read_unlock+0x21/0x23
[<ffffffff810c999f>] find_get_pages_tag+0xc1/0xed
[<ffffffff811c9e68>] ? start_this_handle+0x605/0x64d
[<ffffffff810d3480>] pagevec_lookup_tag+0x20/0x29
[<ffffffff811979e7>] write_cache_pages_da+0xeb/0x37b
[<ffffffff811ca10d>] ? jbd2_journal_start+0xe/0x10
[<ffffffff811aafae>] ? ext4_journal_start_sb+0x115/0x124
[<ffffffff81197f65>] ext4_da_writepages+0x2ee/0x565
[<ffffffff810d2ccf>] do_writepages+0x1f/0x28
[<ffffffff810ca39c>] __filemap_fdatawrite_range+0x4e/0x50
[<ffffffff810ca8a6>] filemap_flush+0x17/0x19
[<ffffffff81193447>] ext4_alloc_da_blocks+0x81/0xab
[<ffffffff8118d669>] ext4_release_file+0x35/0xb3
[<ffffffff8111b07c>] fput+0x117/0x1b2
[<ffffffff81117b56>] filp_close+0x6d/0x78
[<ffffffff8104c2f7>] put_files_struct+0xca/0x190
[<ffffffff8104c403>] exit_files+0x46/0x4e
[<ffffffff8104deb7>] do_exit+0x2b5/0x760
[<ffffffff81119196>] ? fsnotify_modify+0x5d/0x65
[<ffffffff8147f33d>] ? retint_swapgs+0x13/0x1b
[<ffffffff8104e3e0>] do_group_exit+0x7e/0xa9
[<ffffffff8104e41d>] sys_exit_group+0x12/0x16
[<ffffffff81484fd2>] system_call_fastpath+0x16/0x1b
Thanks,
Ben
--
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc http://www.candelatech.com
reply other threads:[~2011-07-12 20:51 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4E1CB3CB.5070108@candelatech.com \
--to=greearb@candelatech.com \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.