[nfs] process locks in "bo_wwait" on 6.4

[pluknet]

2009/6/29 Attilio Rao <attilio at freebsd.org>:
> 2009/6/29 pluknet <pluknet at gmail.com>:
>> 2009/6/29 Attilio Rao <attilio at freebsd.org>:
>>> 2009/6/29 pluknet <pluknet at gmail.com>:
>>>> 2009/6/26 pluknet <pluknet at gmail.com>:
>>>>> 2009/6/26 pluknet <pluknet at gmail.com>:
>>>>>> Hello.
>>>>>>
>>>>>> While building a module on nfs mounted /usr/src
>>>>>> I got an unkillable process waiting forever in bo_wwait.
>>>>>
>>>>> Small note: iface on NFS server has mtu changed from 1500 to 1450.
>>>>> Can this be a source of the problem?
>>>>
>>>> This is 100% reproducible. Lock in the same place. Any hints?
>>>
>>> Can you also show the value of ps?
>>> A precise map of what processes are doing would give an help.
>>> Also would be useful to printout traces for other threads and not only
>>> the stucked one.
>>>
>>
>> >From another run:
>
> I'm unable to see who would be locking the buffer object in question.
> Do you have INVARIANT_SUPPORT/INVARIANTS on?

Yes, I do both.

> What revision of /usr/src/sys/kern/vfs_bio.c are you running with?
>

As of 6.4-R: CVS rev 1.491.2.12.4.1 / SVN rev 183531.

-- 
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