From: Ben Greear <greearb@candelatech.com>
To: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Lockdep splat in 3.0.0-rc4
Date: Fri, 24 Jun 2011 15:05:05 -0700 [thread overview]
Message-ID: <4E050A11.4060807@candelatech.com> (raw)
There are some patches to NFS in this kernel, but I don't think it
has anything to do with this lockdep splat.
I'm not too sure what was happening on this system when this splat
happened.
======================================================
[ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ]
3.0.0-rc4+ #1
------------------------------------------------------
ps/30182 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
(&lock->wait_lock){+.+...}, at: [<ffffffff8147da68>] rt_mutex_slowunlock+0x1d/0xdd
and this task is already holding:
(&(&sighand->siglock)->rlock){-.....}, at: [<ffffffff8105a357>] __lock_task_sighand+0x6e/0x9c
which would create a new lock dependency:s
(&(&sighand->siglock)->rlock){-.....} -> (&lock->wait_lock){+.+...}
but this new dependency connects a HARDIRQ-irq-safe lock:
(&(&sighand->siglock)->rlock){-.....}
... which became HARDIRQ-irq-safe at:
[<ffffffff8107a1c8>] __lock_acquire+0x2b4/0xdd5
[<ffffffff8107b1ed>] lock_acquire+0xf4/0x14b
[<ffffffff8147e02d>] _raw_spin_lock_irqsave+0x4e/0x60
[<ffffffff8105a357>] __lock_task_sighand+0x6e/0x9c
[<ffffffff8105b0f3>] do_send_sig_info+0x27/0x70
[<ffffffff8105b3cf>] group_send_sig_info+0x4c/0x57
[<ffffffff8105b419>] kill_pid_info+0x3f/0x5a
[<ffffffff8104eb39>] it_real_fn+0x85/0xb4
[<ffffffff8106a40c>] __run_hrtimer+0xbe/0x1be
[<ffffffff8106a830>] hrtimer_interrupt+0xe5/0x1c0
[<ffffffff8102328c>] smp_apic_timer_interrupt+0x80/0x93
[<ffffffff81485293>] apic_timer_interrupt+0x13/0x20
[<ffffffff810e7d2c>] copy_page_range+0x29b/0x348
[<ffffffff8104802a>] dup_mm+0x32b/0x46b
[<ffffffff81048cfe>] copy_process+0xb53/0x1323
[<ffffffff810495d9>] do_fork+0x10b/0x2f1
[<ffffffff81010d4a>] sys_clone+0x23/0x25
[<ffffffff81484bf3>] stub_clone+0x13/0x20
to a HARDIRQ-irq-unsafe lock:
(&lock->wait_lock){+.+...}
... which became HARDIRQ-irq-unsafe at:
... [<ffffffff8107a23c>] __lock_acquire+0x328/0xdd5
[<ffffffff8107b1ed>] lock_acquire+0xf4/0x14b
[<ffffffff8147df19>] _raw_spin_lock+0x36/0x45
[<ffffffff8147db77>] rt_mutex_slowlock+0x2b/0x132
[<ffffffff8147dd1c>] rt_mutex_lock+0x46/0x4a
[<ffffffff810a68e9>] rcu_boost_kthread+0x125/0x169
[<ffffffff81066e10>] kthread+0x7d/0x85
[<ffffffff814859e4>] kernel_thread_helper+0x4/0x10
other info that might help us debug this:
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&lock->wait_lock);
local_irq_disable();
lock(&(&sighand->siglock)->rlock);
lock(&lock->wait_lock);
<Interrupt>
lock(&(&sighand->siglock)->rlock);
*** DEADLOCK ***
2 locks held by ps/30182:
#0: (&p->lock){+.+.+.}, at: [<ffffffff811345f0>] seq_read+0x38/0x368
#1: (&(&sighand->siglock)->rlock){-.....}, at: [<ffffffff8105a357>] __lock_task_sighand+0x6e/0x9c
the dependencies between HARDIRQ-irq-safe lock and the holding lock:
-> (&(&sighand->siglock)->rlock){-.....} ops: 24900587 {
IN-HARDIRQ-W at:
[<ffffffff8107a1c8>] __lock_acquire+0x2b4/0xdd5
[<ffffffff8107b1ed>] lock_acquire+0xf4/0x14b
[<ffffffff8147e02d>] _raw_spin_lock_irqsave+0x4e/0x60
[<ffffffff8105a357>] __lock_task_sighand+0x6e/0x9c
[<ffffffff8105b0f3>] do_send_sig_info+0x27/0x70
[<ffffffff8105b3cf>] group_send_sig_info+0x4c/0x57
[<ffffffff8105b419>] kill_pid_info+0x3f/0x5a
[<ffffffff8104eb39>] it_real_fn+0x85/0xb4
[<ffffffff8106a40c>] __run_hrtimer+0xbe/0x1be
[<ffffffff8106a830>] hrtimer_interrupt+0xe5/0x1c0
[<ffffffff8102328c>] smp_apic_timer_interrupt+0x80/0x93
[<ffffffff81485293>] apic_timer_interrupt+0x13/0x20
[<ffffffff810e7d2c>] copy_page_range+0x29b/0x348
[<ffffffff8104802a>] dup_mm+0x32b/0x46b
[<ffffffff81048cfe>] copy_process+0xb53/0x1323
[<ffffffff810495d9>] do_fork+0x10b/0x2f1
[<ffffffff81010d4a>] sys_clone+0x23/0x25
[<ffffffff81484bf3>] stub_clone+0x13/0x20
INITIAL USE at:
[<ffffffff8107a2b3>] __lock_acquire+0x39f/0xdd5
[<ffffffff8107b1ed>] lock_acquire+0xf4/0x14b
[<ffffffff8147e02d>] _raw_spin_lock_irqsave+0x4e/0x60
[<ffffffff8105a4bf>] flush_signals+0x1d/0x43
[<ffffffff8105a50d>] ignore_signals+0x28/0x2a
[<ffffffff81066e56>] kthreadd+0x3e/0x13d
[<ffffffff814859e4>] kernel_thread_helper+0x4/0x10
}
... key at: [<ffffffff81c45510>] __key.56507+0x0/0x8
... acquired at:
[<ffffffff81079bf6>] check_irq_usage+0x5d/0xbe
[<ffffffff8107aa1d>] __lock_acquire+0xb09/0xdd5
[<ffffffff8107b1ed>] lock_acquire+0xf4/0x14b
[<ffffffff8147df19>] _raw_spin_lock+0x36/0x45
[<ffffffff8147da68>] rt_mutex_slowunlock+0x1d/0xdd
[<ffffffff8147db4a>] rt_mutex_unlock+0x22/0x24
[<ffffffff810a7d21>] __rcu_read_unlock+0x1c0/0x24e
[<ffffffff8105a287>] rcu_read_unlock+0x21/0x23
[<ffffffff8105a376>] __lock_task_sighand+0x8d/0x9c
[<ffffffff8116c56a>] do_task_stat+0x11d/0x84a
[<ffffffff8116cca6>] proc_tgid_stat+0xf/0x11
[<ffffffff811699f1>] proc_single_show+0x54/0x71
[<ffffffff81134739>] seq_read+0x181/0x368
[<ffffffff811199e2>] vfs_read+0xa6/0x102
[<ffffffff81119af7>] sys_read+0x45/0x6c
[<ffffffff81484852>] system_call_fastpath+0x16/0x1b
the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock:
-> (&lock->wait_lock){+.+...} ops: 594 {
HARDIRQ-ON-W at:
[<ffffffff8107a23c>] __lock_acquire+0x328/0xdd5
[<ffffffff8107b1ed>] lock_acquire+0xf4/0x14b
[<ffffffff8147df19>] _raw_spin_lock+0x36/0x45
[<ffffffff8147db77>] rt_mutex_slowlock+0x2b/0x132
[<ffffffff8147dd1c>] rt_mutex_lock+0x46/0x4a
[<ffffffff810a68e9>] rcu_boost_kthread+0x125/0x169
[<ffffffff81066e10>] kthread+0x7d/0x85
[<ffffffff814859e4>] kernel_thread_helper+0x4/0x10
SOFTIRQ-ON-W at:
[<ffffffff8107a25d>] __lock_acquire+0x349/0xdd5
[<ffffffff8107b1ed>] lock_acquire+0xf4/0x14b
[<ffffffff8147df19>] _raw_spin_lock+0x36/0x45
[<ffffffff8147db77>] rt_mutex_slowlock+0x2b/0x132
[<ffffffff8147dd1c>] rt_mutex_lock+0x46/0x4a
[<ffffffff810a68e9>] rcu_boost_kthread+0x125/0x169
[<ffffffff81066e10>] kthread+0x7d/0x85
[<ffffffff814859e4>] kernel_thread_helper+0x4/0x10
INITIAL USE at:
[<ffffffff8107a2b3>] __lock_acquire+0x39f/0xdd5
[<ffffffff8107b1ed>] lock_acquire+0xf4/0x14b
[<ffffffff8147df19>] _raw_spin_lock+0x36/0x45
[<ffffffff8147db77>] rt_mutex_slowlock+0x2b/0x132
[<ffffffff8147dd1c>] rt_mutex_lock+0x46/0x4a
[<ffffffff810a68e9>] rcu_boost_kthread+0x125/0x169
[<ffffffff81066e10>] kthread+0x7d/0x85
[<ffffffff814859e4>] kernel_thread_helper+0x4/0x10
}
... key at: [<ffffffff824759a0>] __key.22188+0x0/0x8
... acquired at:
[<ffffffff81079bf6>] check_irq_usage+0x5d/0xbe
[<ffffffff8107aa1d>] __lock_acquire+0xb09/0xdd5
[<ffffffff8107b1ed>] lock_acquire+0xf4/0x14b
[<ffffffff8147df19>] _raw_spin_lock+0x36/0x45
[<ffffffff8147da68>] rt_mutex_slowunlock+0x1d/0xdd
[<ffffffff8147db4a>] rt_mutex_unlock+0x22/0x24
[<ffffffff810a7d21>] __rcu_read_unlock+0x1c0/0x24e
[<ffffffff8105a287>] rcu_read_unlock+0x21/0x23
[<ffffffff8105a376>] __lock_task_sighand+0x8d/0x9c
[<ffffffff8116c56a>] do_task_stat+0x11d/0x84a
[<ffffffff8116cca6>] proc_tgid_stat+0xf/0x11
[<ffffffff811699f1>] proc_single_show+0x54/0x71
[<ffffffff81134739>] seq_read+0x181/0x368
[<ffffffff811199e2>] vfs_read+0xa6/0x102
[<ffffffff81119af7>] sys_read+0x45/0x6c
[<ffffffff81484852>] system_call_fastpath+0x16/0x1b
stack backtrace:
Pid: 30182, comm: ps Not tainted 3.0.0-rc4+ #1
Call Trace:
[<ffffffff8147e57b>] ? _raw_spin_unlock_irqrestore+0x6b/0x79
[<ffffffff81079b85>] check_usage+0x364/0x378
[<ffffffff81079bf6>] check_irq_usage+0x5d/0xbe
[<ffffffff8107aa1d>] __lock_acquire+0xb09/0xdd5
[<ffffffff810a6e6d>] ? rcu_start_gp+0x2e7/0x310
[<ffffffff8147da68>] ? rt_mutex_slowunlock+0x1d/0xdd
[<ffffffff8107b1ed>] lock_acquire+0xf4/0x14b
[<ffffffff8147da68>] ? rt_mutex_slowunlock+0x1d/0xdd
[<ffffffff8147df19>] _raw_spin_lock+0x36/0x45
[<ffffffff8147da68>] ? rt_mutex_slowunlock+0x1d/0xdd
[<ffffffff8147da68>] rt_mutex_slowunlock+0x1d/0xdd
[<ffffffff8147db4a>] rt_mutex_unlock+0x22/0x24
[<ffffffff810a7d21>] __rcu_read_unlock+0x1c0/0x24e
[<ffffffff8105a287>] rcu_read_unlock+0x21/0x23
[<ffffffff8105a376>] __lock_task_sighand+0x8d/0x9c
[<ffffffff8116c56a>] do_task_stat+0x11d/0x84a
[<ffffffff81077c0b>] ? register_lock_class+0x1e/0x336
[<ffffffff81078c91>] ? mark_lock+0x2d/0x22d
[<ffffffff81078c91>] ? mark_lock+0x2d/0x22d
[<ffffffff8107a2b3>] ? __lock_acquire+0x39f/0xdd5
[<ffffffff8110529a>] ? add_partial+0x1b/0x53
[<ffffffff81063bb3>] ? cpumask_weight+0xe/0xe
[<ffffffff8116cca6>] proc_tgid_stat+0xf/0x11
[<ffffffff811699f1>] proc_single_show+0x54/0x71
[<ffffffff81134739>] seq_read+0x181/0x368
[<ffffffff811199e2>] vfs_read+0xa6/0x102
[<ffffffff8111a031>] ? fget_light+0x35/0xac
[<ffffffff81119af7>] sys_read+0x45/0x6c
[<ffffffff81484852>] system_call_fastpath+0x16/0x1b
--
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc http://www.candelatech.com
reply other threads:[~2011-06-24 22:05 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=4E050A11.4060807@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.