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Date: Wed, 6 Aug 2008 09:51:14 +0800
From: "Dave Young" <hidave.darkstar@gmail.com>
To: "Bob Copeland" <me@bobcopeland.com>
Subject: Re: [BUG] wireless : cpu stuck for 61s
Cc: "Jiri Slaby" <jirislaby@gmail.com>,
	"Pekka J Enberg" <penberg@cs.helsinki.fi>,
	"Andrew Morton" <akpm@linux-foundation.org>,
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On Tue, Aug 5, 2008 at 8:24 PM, Bob Copeland <me@bobcopeland.com> wrote:
> On Tue, Aug 05, 2008 at 09:29:26AM +0800, Dave Young wrote:
>> With the patch I cann't reproduce the bug with 27-rc1 now.
>>
>> >  [<c02375a6>] ? debugfs_create_file+0x46/0x210
>> >  [<c02375a6>] ? debugfs_create_file+0x46/0x210
>> >  [<c02375a6>] debugfs_create_file+0x46/0x210
>> >  [<c02377f1>] debugfs_create_dir+0x21/0x30
>> >  [<f8901f6d>] ieee80211_sta_debugfs_add+0x2d/0x150 [mac80211]
>> >  [<f88eba89>] sta_info_debugfs_add_work+0x89/0x130 [mac80211]
>> >  [<f890a170>] ? rate_control_pid_add_sta_debugfs+0x0/0x30 [mac80211]
>
> I wonder if there were two separate problems here.  I looked into
> this with some detail yesterday and agree with Johannes that the above
> trace is on locking the parent directory's i_mutex, but I too couldn't
> see any problems with sta_info_debugfs_add_work.  Other stuff could also
> modify the directory with or without rtnl_lock, but not in a way that
> to my untrained eyes would lead to deadlock.

Yes,. I think so. It's the original bug for me, while testing I found
the mutex deadlock problem.

But this week I will have no time to trace it. so if I have time I
will keep tracing the problem

>
> Or is the trace just wrong?
>
> --
> Bob Copeland %% www.bobcopeland.com
>
>



-- 
Regards
dave