Re: INFO: possible recursive locking detected ps2_command

(cc linux-input)

On Thu, 31 Jul 2008 11:41:25 +0200
"Zdenek Kabelac" [off-list ref] wrote:

Hi

During mouse unplugging from psaux connector from the laptops' docking
station I've got attached INFO trace.
(laptops still has synaptics device)

Also for unknown reason to me  psaux mouse & synaptic device do not
work somehow together - is it hw limitation
of /dev/input/mice  interface?
(USB mouse and synaptics do work quite well together)

[ INFO: possible recursive locking detected ]
2.6.27-rc1 #48

(it's 2.6.27-rc1)

---------------------------------------------
kseriod/166 is trying to acquire lock:
 (&ps2dev->cmd_mutex){--..}, at: [<ffffffff8126e9ae>] ps2_command+0x5e/0x460

but task is already holding lock:
 (&ps2dev->cmd_mutex){--..}, at: [<ffffffff8126e9ae>] ps2_command+0x5e/0x460

other info that might help us debug this:
4 locks held by kseriod/166:
 #0:  (serio_mutex){--..}, at: [<ffffffff8126cc1e>] serio_thread+0x3e/0x410
 #1:  (&serio->drv_mutex){--..}, at: [<ffffffff8126bf8b>]
serio_connect_driver+0x2b/0x50
 #2:  (psmouse_mutex){--..}, at: [<ffffffffa009aa00>]
psmouse_connect+0x30/0x2c0 [psmouse]
 #3:  (&ps2dev->cmd_mutex){--..}, at: [<ffffffff8126e9ae>]
ps2_command+0x5e/0x460

stack backtrace:
Pid: 166, comm: kseriod Not tainted 2.6.27-rc1 #48

Call Trace:
 [<ffffffff81068bda>] __lock_acquire+0xcea/0x13b0
 [<ffffffff81066401>] ? trace_hardirqs_off_caller+0x21/0xc0
 [<ffffffff810664ad>] ? trace_hardirqs_off+0xd/0x10
 [<ffffffff8126e9ae>] ? ps2_command+0x5e/0x460
 [<ffffffff81069336>] lock_acquire+0x96/0xe0
 [<ffffffff8126e9ae>] ? ps2_command+0x5e/0x460
 [<ffffffff81313861>] mutex_lock_nested+0xc1/0x340
 [<ffffffff8126e9ae>] ? ps2_command+0x5e/0x460
 [<ffffffff810135a0>] ? native_sched_clock+0x90/0xb0
 [<ffffffff8126e9ae>] ps2_command+0x5e/0x460
 [<ffffffff81066401>] ? trace_hardirqs_off_caller+0x21/0xc0
 [<ffffffff81065834>] ? get_lock_stats+0x34/0x70
 [<ffffffffa009977d>] psmouse_sliced_command+0x2d/0x90 [psmouse]
 [<ffffffff8126e838>] ? ps2_sendbyte+0x48/0x130
 [<ffffffffa009b8f7>] synaptics_pt_write+0x27/0x60 [psmouse]
 [<ffffffff81315acd>] ? _spin_unlock_irq+0x3d/0x80
 [<ffffffff8126e84d>] ps2_sendbyte+0x5d/0x130
 [<ffffffff81319840>] ? sub_preempt_count+0x80/0x120
 [<ffffffff8126ea4d>] ps2_command+0xfd/0x460
 [<ffffffff81319840>] ? sub_preempt_count+0x80/0x120
 [<ffffffff81315acd>] ? _spin_unlock_irq+0x3d/0x80
 [<ffffffffa0099917>] psmouse_probe+0x27/0xa0 [psmouse]
 [<ffffffff8126c1e1>] ? serio_open+0x11/0x50
 [<ffffffffa009ab48>] psmouse_connect+0x178/0x2c0 [psmouse]
 [<ffffffff8126bf96>] serio_connect_driver+0x36/0x50
 [<ffffffff8126bfcb>] serio_driver_probe+0x1b/0x20
 [<ffffffff81221112>] driver_probe_device+0xa2/0x1e0
 [<ffffffff812212e0>] ? __device_attach+0x0/0x10
 [<ffffffff812212e9>] __device_attach+0x9/0x10
 [<ffffffff8122050b>] bus_for_each_drv+0x6b/0xa0
 [<ffffffff812213b8>] device_attach+0x88/0x90
 [<ffffffff812202d5>] bus_attach_device+0x55/0x80
 [<ffffffff8121ee99>] device_add+0x4f9/0x610
 [<ffffffff81319840>] ? sub_preempt_count+0x80/0x120
 [<ffffffff8126ce1c>] serio_thread+0x23c/0x410
 [<ffffffff810571a0>] ? autoremove_wake_function+0x0/0x40
 [<ffffffff8126cbe0>] ? serio_thread+0x0/0x410
 [<ffffffff81056de9>] kthread+0x49/0x90
 [<ffffffff8100d669>] child_rip+0xa/0x11
 [<ffffffff8103b757>] ? finish_task_switch+0x57/0x110
 [<ffffffff81315acd>] ? _spin_unlock_irq+0x3d/0x80
 [<ffffffff8100cc73>] ? restore_args+0x0/0x30
 [<ffffffff810664ad>] ? trace_hardirqs_off+0xd/0x10
 [<ffffffff81056da0>] ? kthread+0x0/0x90
 [<ffffffff8100d65f>] ? child_rip+0x0/0x11