All of lore.kernel.org
 help / color / mirror / Atom feed
From: Antti Palosaari <crope@iki.fi>
To: Mauro Carvalho Chehab <m.chehab@samsung.com>,
	LMML <linux-media@vger.kernel.org>
Cc: "Frank Schäfer" <fschaefer.oss@googlemail.com>
Subject: em28xx lock debug *** DEADLOCK ***
Date: Fri, 30 Aug 2013 22:27:14 +0300	[thread overview]
Message-ID: <5220F212.9030108@iki.fi> (raw)

Mauro,
I was thinking you already fixed that one, but I just meet it with 
latest media tree 3.11.0-rc2+ when I unplugged device ?

regards
Antti

[ 1464.238906] usb 2-2: USB disconnect, device number 2
[ 1464.242123] em28178 #0: disconnecting em28178 #0 video
[ 1464.242254]
[ 1464.242261] ======================================================
[ 1464.242265] [ INFO: possible circular locking dependency detected ]
[ 1464.242272] 3.11.0-rc2+ #61 Tainted: G         C O
[ 1464.242277] -------------------------------------------------------
[ 1464.242283] khubd/46 is trying to acquire lock:
[ 1464.242288]  (em28xx_devlist_mutex){+.+.+.}, at: [<ffffffffa04b1c8d>] 
em28xx_close_extension+0x1d/0x70 [em28xx]
[ 1464.242316]
[ 1464.242316] but task is already holding lock:
[ 1464.242322]  (&dev->lock){+.+.+.}, at: [<ffffffffa04af7a9>] 
em28xx_usb_disconnect+0x99/0x140 [em28xx]
[ 1464.242342]
[ 1464.242342] which lock already depends on the new lock.
[ 1464.242342]
[ 1464.242349]
[ 1464.242349] the existing dependency chain (in reverse order) is:
[ 1464.242354]
[ 1464.242354] -> #1 (&dev->lock){+.+.+.}:
[ 1464.242365]        [<ffffffff810c27be>] lock_acquire+0x8e/0x130
[ 1464.242376]        [<ffffffff8168dc25>] mutex_lock_nested+0x85/0x390
[ 1464.242386]        [<ffffffffa050c659>] em28xx_dvb_init+0x79/0x1c60 
[em28xx_dvb]
[ 1464.242396]        [<ffffffffa04afa68>] 
em28xx_register_extension+0x58/0xa0 [em28xx]
[ 1464.242410]        [<ffffffffa0514010>] 0xffffffffa0514010
[ 1464.242429]        [<ffffffff810002fa>] do_one_initcall+0xfa/0x1b0
[ 1464.242439]        [<ffffffff810d1166>] load_module+0x1de6/0x2760
[ 1464.242447]        [<ffffffff810d1bb7>] SyS_init_module+0xd7/0x120
[ 1464.242455]        [<ffffffff8169c5d4>] tracesys+0xdd/0xe2
[ 1464.242465]
[ 1464.242465] -> #0 (em28xx_devlist_mutex){+.+.+.}:
[ 1464.242475]        [<ffffffff810c2060>] __lock_acquire+0x1db0/0x1ea0
[ 1464.242483]        [<ffffffff810c27be>] lock_acquire+0x8e/0x130
[ 1464.242490]        [<ffffffff8168dc25>] mutex_lock_nested+0x85/0x390
[ 1464.242498]        [<ffffffffa04b1c8d>] 
em28xx_close_extension+0x1d/0x70 [em28xx]
[ 1464.242513]        [<ffffffffa04af7c3>] 
em28xx_usb_disconnect+0xb3/0x140 [em28xx]
[ 1464.242525]        [<ffffffff814939e3>] usb_unbind_interface+0x63/0x1b0
[ 1464.242536]        [<ffffffff814035af>] __device_release_driver+0x7f/0xf0
[ 1464.242545]        [<ffffffff8140390e>] device_release_driver+0x2e/0x40
[ 1464.242554]        [<ffffffff81403040>] bus_remove_device+0x110/0x190
[ 1464.242563]        [<ffffffff813ffefd>] device_del+0x13d/0x1d0
[ 1464.242570]        [<ffffffff814912e0>] usb_disable_device+0xb0/0x270
[ 1464.242579]        [<ffffffff81487655>] usb_disconnect+0xb5/0x1d0
[ 1464.242589]        [<ffffffff81488e69>] 
hub_port_connect_change+0xc9/0xad0
[ 1464.242598]        [<ffffffff81489b68>] hub_events+0x2f8/0x940
[ 1464.242607]        [<ffffffff8148a1e5>] hub_thread+0x35/0x190
[ 1464.242616]        [<ffffffff8107f99d>] kthread+0xed/0x100
[ 1464.242625]        [<ffffffff8169c31c>] ret_from_fork+0x7c/0xb0
[ 1464.242635]
[ 1464.242635] other info that might help us debug this:
[ 1464.242635]
[ 1464.242642]  Possible unsafe locking scenario:
[ 1464.242642]
[ 1464.242647]        CPU0                    CPU1
[ 1464.242651]        ----                    ----
[ 1464.242655]   lock(&dev->lock);
[ 1464.242663]                                lock(em28xx_devlist_mutex);
[ 1464.242669]                                lock(&dev->lock);
[ 1464.242676]   lock(em28xx_devlist_mutex);
[ 1464.242683]
[ 1464.242683]  *** DEADLOCK ***
[ 1464.242683]
[ 1464.242691] 4 locks held by khubd/46:
[ 1464.242695]  #0:  (&__lockdep_no_validate__){......}, at: 
[<ffffffff81489924>] hub_events+0xb4/0x940
[ 1464.242713]  #1:  (&__lockdep_no_validate__){......}, at: 
[<ffffffff81487606>] usb_disconnect+0x66/0x1d0
[ 1464.242730]  #2:  (&__lockdep_no_validate__){......}, at: 
[<ffffffff81403906>] device_release_driver+0x26/0x40
[ 1464.242746]  #3:  (&dev->lock){+.+.+.}, at: [<ffffffffa04af7a9>] 
em28xx_usb_disconnect+0x99/0x140 [em28xx]
[ 1464.242767]
[ 1464.242767] stack backtrace:
[ 1464.242777] CPU: 3 PID: 46 Comm: khubd Tainted: G         C O 
3.11.0-rc2+ #61
[ 1464.242783] Hardware name: System manufacturer System Product 
Name/M5A78L-M/USB3, BIOS 1503    11/14/2012
[ 1464.242788]  ffffffff8227a650 ffff88030dbf7858 ffffffff8168a207 
0000000000000007
[ 1464.242800]  ffffffff8227a650 ffff88030dbf78a8 ffffffff81684141 
ffff88030dbd2bc8
[ 1464.242811]  ffff88030dbf7938 ffff88030dbf78a8 ffff88030dbd2b90 
0af05782bc9fa503
[ 1464.242823] Call Trace:
[ 1464.242836]  [<ffffffff8168a207>] dump_stack+0x55/0x76
[ 1464.242846]  [<ffffffff81684141>] print_circular_bug+0x1fb/0x20c
[ 1464.242857]  [<ffffffff810c2060>] __lock_acquire+0x1db0/0x1ea0
[ 1464.242866]  [<ffffffff810c06e0>] ? __lock_acquire+0x430/0x1ea0
[ 1464.242878]  [<ffffffff81693500>] ? _raw_spin_unlock_irq+0x30/0x50
[ 1464.242887]  [<ffffffff810c27be>] lock_acquire+0x8e/0x130
[ 1464.242902]  [<ffffffffa04b1c8d>] ? em28xx_close_extension+0x1d/0x70 
[em28xx]
[ 1464.242911]  [<ffffffff810be94b>] ? mark_held_locks+0xbb/0x140
[ 1464.242920]  [<ffffffff8168de5b>] ? mutex_lock_nested+0x2bb/0x390
[ 1464.242928]  [<ffffffff8168dc25>] mutex_lock_nested+0x85/0x390
[ 1464.242943]  [<ffffffffa04b1c8d>] ? em28xx_close_extension+0x1d/0x70 
[em28xx]
[ 1464.242957]  [<ffffffffa04b1c8d>] ? em28xx_close_extension+0x1d/0x70 
[em28xx]
[ 1464.242971]  [<ffffffffa04af7a9>] ? em28xx_usb_disconnect+0x99/0x140 
[em28xx]
[ 1464.242985]  [<ffffffffa04b1c8d>] em28xx_close_extension+0x1d/0x70 
[em28xx]
[ 1464.242999]  [<ffffffffa04af7c3>] em28xx_usb_disconnect+0xb3/0x140 
[em28xx]
[ 1464.243009]  [<ffffffff814939e3>] usb_unbind_interface+0x63/0x1b0
[ 1464.243018]  [<ffffffff814035af>] __device_release_driver+0x7f/0xf0
[ 1464.243027]  [<ffffffff8140390e>] device_release_driver+0x2e/0x40
[ 1464.243036]  [<ffffffff81403040>] bus_remove_device+0x110/0x190
[ 1464.243044]  [<ffffffff813ffefd>] device_del+0x13d/0x1d0
[ 1464.243052]  [<ffffffff814912e0>] usb_disable_device+0xb0/0x270
[ 1464.243062]  [<ffffffff8119abd5>] ? kfree+0xa5/0x1d0
[ 1464.243072]  [<ffffffff81487655>] usb_disconnect+0xb5/0x1d0
[ 1464.243082]  [<ffffffff81488e69>] hub_port_connect_change+0xc9/0xad0
[ 1464.243090]  [<ffffffff81490906>] ? usb_control_msg+0xe6/0x120
[ 1464.243100]  [<ffffffff81489b68>] hub_events+0x2f8/0x940
[ 1464.243110]  [<ffffffff8148a1e5>] hub_thread+0x35/0x190
[ 1464.243118]  [<ffffffff8107fed0>] ? wake_up_bit+0x40/0x40
[ 1464.243128]  [<ffffffff8148a1b0>] ? hub_events+0x940/0x940
[ 1464.243136]  [<ffffffff8107f99d>] kthread+0xed/0x100
[ 1464.243147]  [<ffffffff8107f8b0>] ? kthread_create_on_node+0x160/0x160
[ 1464.243156]  [<ffffffff8169c31c>] ret_from_fork+0x7c/0xb0
[ 1464.243165]  [<ffffffff8107f8b0>] ? kthread_create_on_node+0x160/0x160
[ 1464.243214] em28178 #0: V4L2 device video0 deregistered
[ 1466.303859] Em28xx: Removed (Em28xx dvb Extension) extension


-- 
http://palosaari.fi/

                 reply	other threads:[~2013-08-30 19:28 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=5220F212.9030108@iki.fi \
    --to=crope@iki.fi \
    --cc=fschaefer.oss@googlemail.com \
    --cc=linux-media@vger.kernel.org \
    --cc=m.chehab@samsung.com \
    /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.