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From: Robert Watson <rwatson@FreeBSD.org>
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To: Roman Divacky <rdivacky@FreeBSD.org>
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Cc: Kostik Belousov <kostikbel@gmail.com>, Randy Bush <randy@psg.com>,
	Bartosz Stec <admin@kkip.pl>, FreeBSD Current <current@FreeBSD.org>
Subject: Re: panic: sleeping thread & bufwrite: buffer is not busy???
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On Fri, 12 Dec 2008, Roman Divacky wrote:

>>> You are mixing the issues without a reason. To claim that you problem is 
>>> similar, you need to show the similar backtrace. The panic shown is the 
>>> late manifestation of a problem, it is kind a catch-all for some sort of 
>>> locking issues.
>>
>> This is the second report of weird rwlock-related panics in a week.  We 
>> should read the code on this one closely, but I can't help but notice that 
>> it's similar to Roman's report of an rwlock-related panic.  Was there a 
>> locking/scheduling change in the last week or two in -current that could 
>> explain these symptoms?
>
> I still have the vmcore from the crash... can it help?

I think the most important thing is to see the contents of *inp and 
*inp->inp_lock.lock_object.

Robert N M Watson
Computer Laboratory
University of Cambridge