From: Andrew Morton <akpm@osdl.org>
To: Dave Jones <davej@redhat.com>
Cc: Linux Kernel <linux-kernel@vger.kernel.org>,
Arjan van de Ven <arjan@infradead.org>,
Ingo Molnar <mingo@elte.hu>
Subject: Re: workqueue lockdep bug.
Date: Mon, 14 Aug 2006 23:36:26 -0700 [thread overview]
Message-ID: <20060814233626.1e3c41b2.akpm@osdl.org> (raw)
In-Reply-To: <20060814183319.GJ15569@redhat.com>
On Mon, 14 Aug 2006 14:33:19 -0400
Dave Jones <davej@redhat.com> wrote:
> Andrew,
> I merged the workqueue changes from -mm into the Fedora-devel kernel to
> kill off those billion cpufreq lockdep warnings. The bug has now mutated
> into this:
>
> (Trimmed version of log from https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=202223)
>
I don't get it.
>
> > Breaking affinity for irq 185
> > Breaking affinity for irq 193
> > Breaking affinity for irq 209
> > CPU 1 is now offline
> > lockdep: not fixing up alternatives.
> >
> > =======================================================
> > [ INFO: possible circular locking dependency detected ]
> > 2.6.17-1.2548.fc6 #1
> > -------------------------------------------------------
> > pm-hibernate/4335 is trying to acquire lock:
> > ((cpu_chain).rwsem){..--}, at: [<c0430fa4>] blocking_notifier_call_chain+0x11/0x2d
> >
> > but task is already holding lock:
> > (workqueue_mutex){--..}, at: [<c0612820>] mutex_lock+0x21/0x24
> >
> > which lock already depends on the new lock.
> >
> >
> > the existing dependency chain (in reverse order) is:
> >
> > -> #1 (workqueue_mutex){--..}:
> > [<c043c08e>] lock_acquire+0x4b/0x6d
> > [<c06126b1>] __mutex_lock_slowpath+0xbc/0x20a
> > [<c0612820>] mutex_lock+0x21/0x24
> > [<c0433c25>] workqueue_cpu_callback+0xfd/0x1ee
> > [<c0614ef5>] notifier_call_chain+0x20/0x31
> > [<c0430fb0>] blocking_notifier_call_chain+0x1d/0x2d
> > [<c043f4c5>] _cpu_down+0x47/0x1c4
> > [<c043f805>] disable_nonboot_cpus+0x9b/0x11a
> > [<c0445b32>] prepare_processes+0xe/0x41
> > [<c0445d87>] pm_suspend_disk+0x9/0xf3
> > [<c0444e12>] enter_state+0x54/0x1b7
> > [<c0444ffb>] state_store+0x86/0x9c
> > [<c04a9f88>] subsys_attr_store+0x20/0x25
> > [<c04aa08c>] sysfs_write_file+0xab/0xd1
> > [<c04732cb>] vfs_write+0xab/0x157
> > [<c0473910>] sys_write+0x3b/0x60
> > [<c0403faf>] syscall_call+0x7/0xb
cpu_add_remove_lock -> cpu_chain.rwsem -> workqueue_mutex
> > -> #0 ((cpu_chain).rwsem){..--}:
> > [<c043c08e>] lock_acquire+0x4b/0x6d
> > [<c04390a0>] down_read+0x2d/0x40
> > [<c0430fa4>] blocking_notifier_call_chain+0x11/0x2d
> > [<c043f5aa>] _cpu_down+0x12c/0x1c4
> > [<c043f805>] disable_nonboot_cpus+0x9b/0x11a
> > [<c0445b32>] prepare_processes+0xe/0x41
> > [<c0445d87>] pm_suspend_disk+0x9/0xf3
> > [<c0444e12>] enter_state+0x54/0x1b7
> > [<c0444ffb>] state_store+0x86/0x9c
> > [<c04a9f88>] subsys_attr_store+0x20/0x25
> > [<c04aa08c>] sysfs_write_file+0xab/0xd1
> > [<c04732cb>] vfs_write+0xab/0x157
> > [<c0473910>] sys_write+0x3b/0x60
> > [<c0403faf>] syscall_call+0x7/0xb
cpu_add_remove_lock -> cpu_chain.rwsem
> > other info that might help us debug this:
> >
> > 2 locks held by pm-hibernate/4335:
> > #0: (cpu_add_remove_lock){--..}, at: [<c0612820>] mutex_lock+0x21/0x24
> > #1: (workqueue_mutex){--..}, at: [<c0612820>] mutex_lock+0x21/0x24
> >
> > stack backtrace:
> > [<c04051ee>] show_trace_log_lvl+0x58/0x159
> > [<c04057ea>] show_trace+0xd/0x10
> > [<c0405903>] dump_stack+0x19/0x1b
> > [<c043b176>] print_circular_bug_tail+0x59/0x64
> > [<c043b98e>] __lock_acquire+0x80d/0x99c
> > [<c043c08e>] lock_acquire+0x4b/0x6d
> > [<c04390a0>] down_read+0x2d/0x40
> > [<c0430fa4>] blocking_notifier_call_chain+0x11/0x2d
> > [<c043f5aa>] _cpu_down+0x12c/0x1c4
> > [<c043f805>] disable_nonboot_cpus+0x9b/0x11a
> > [<c0445b32>] prepare_processes+0xe/0x41
> > [<c0445d87>] pm_suspend_disk+0x9/0xf3
> > [<c0444e12>] enter_state+0x54/0x1b7
> > [<c0444ffb>] state_store+0x86/0x9c
> > [<c04a9f88>] subsys_attr_store+0x20/0x25
> > [<c04aa08c>] sysfs_write_file+0xab/0xd1
> > [<c04732cb>] vfs_write+0xab/0x157
> > [<c0473910>] sys_write+0x3b/0x60
> > [<c0403faf>] syscall_call+0x7/0xb
cpu_add_remove_lock -> cpu_chain.rwsem
I don't see anywhere where this process took workqueue_mutex.
> > DWARF2 unwinder stuck at syscall_call+0x7/0xb
bah.
next prev parent reply other threads:[~2006-08-15 6:36 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-08-14 18:33 Dave Jones
2006-08-15 6:36 ` Andrew Morton [this message]
[not found] ` <3888a5cd0608161631j629ae4a2l929d9b8fead6a2d8@mail.gmail.com>
2006-08-17 1:07 ` Jiri Slaby
2006-08-17 1:17 ` Jiri Slaby
2006-09-08 9:19 ` Jiri Slaby
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=20060814233626.1e3c41b2.akpm@osdl.org \
--to=akpm@osdl.org \
--cc=arjan@infradead.org \
--cc=davej@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®