Re: [2.6.20] BUG: workqueue leaked lock

Jarek Poplawski
2007-03-16T14:45:06Z

On 15-03-2007 20:17, Folkert van Heusden wrote:
>>> On Tue, 13 Mar 2007 17:50:14 +0100 Folkert van Heusden <folkert@vanheusden.com> wrote:
>>> ...
>>> [ 1756.728209] BUG: workqueue leaked lock or atomic: nfsd4/0x00000000/3577
> ...
>>> [ 1846.684023] [<c1003bdb>] kernel_thread_helper+0x7/0x10
>> Oleg, that's a fairly incomprehensible message we have in there. Can you
>> please explain what it means?
>
> Haha ok :-)
>
> Good, since I run 2.6.20 with these debugging switches switched on, I
> get occasionally errors like these. I get ALWAYS the following error
> when the system first boots when the TOR executable is started:
>
> [ 137.324255] =======================================================
> [ 137.324359] [ INFO: possible circular locking dependency detected ]
> [ 137.324412] 2.6.20 #2
> [ 137.324457] -------------------------------------------------------

Hi,

IMHO you should now switch off lockdep ("Lock debuging: ..." options),
until you update or get some patch for this circular problem. Your
logs should be sufficient to nfsd people and lockdep turns off checking
after this anyway. I don't know if this is a known and real locking
problem, but it could be interesting now, if workqueue error would
reapear. It seems nfsd code is breaking somewhere with locks held -
maybe because of problems with lockdep's error handling.

Regards,
Jarek P.