system hangs on shutdown while on wireless (ath) (Was: drm2 and the kernel messages on shutdown)

[Ruslan Mahmatkhanov]

Ruslan Mahmatkhanov wrote on 18.06.2012 13:10:
> Ivan Klymenko wrote on 18.06.2012 13:02:
>> В Mon, 18 Jun 2012 12:35:33 +0400
>> Ruslan Mahmatkhanov <cvs-src at yandex.ru> пишет:
>>
>>> Good day,
>>>
>>> since switching to new drm code (starting at April if I recall
>>> correctly) I'm experiencing sporadic laptop hangs when choose the
>>> shutdown command in UI (gnome) environment. The hdd led isn't
>>> blinking but the laptop is still up. In such cases I forced to
>>> shutdown it by pressing power off button, but at the next system
>>> start it running filesystem checks (yes, with journal but some time
>>> only full fsck is able to fix that). What I'm asking for is - when
>>> there some sysctl or boot loader option will be available to turn on
>>> kernel messages on shutdown? I really want to know on what it hanging
>>> on. I didn't bothered with this while it was available as third-party
>>> patch, but since it is now in -current and enabled by default, I
>>> think this feature should be available. Thanks.
>>>
>>> PS. I'm now subscribed to current at . So do not need to approve my
>>> previous message, that's waiting for moderator approval.
>>>
>>
>> Dear Ruslan.
>> Your problems hang your laptop is not associated with the transition to
>> drm2.
>> And you can see this - when the downgrade to the SVN revision r236313
>>
>> Your problems are now committing to this
>> http://svnweb.freebsd.org/base?view=revision&revision=236317
>>
>> You can check it and make sure my right.
>>
>> Good luck
>
> Thanks Ivan, I'll check it out.  But the request in subject line is
> still valid for me, because the current state make me feels like..
> uhmm.. a blind kitten :)

Hi, I still didn't tried to revert this change to check if it the 
reason. But I realized that I only got this issue when I'm on wireless. 
And I can 100% reproduce this. When using ethernet (re) - system shuts 
down just fine. When using wireless (ath) - it hanging forever.

So it seems like ath deadlock or something (cc:ing Adrian). Would you 
please provide me with instructions on how to debug this, or what info 
should I provide to you to realize this. Thanks.

ath0 at pci0:37:0:0:	class=0x028000 card=0x1461103c chip=0x002b168c 
rev=0x01 hdr=0x00
     vendor     = 'Atheros Communications Inc.'
     device     = 'AR9285 Wireless Network Adapter (PCI-Express)'
     class      = network

My -current is from Sat Jul 14 12:15:20 2012 (svn #238449).

-- 
Regards,
Ruslan

Tinderboxing kills... the drives.