From owner-freebsd-current@FreeBSD.ORG  Thu Jul 11 10:54:48 2013
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 id 1UxEWB-0000il-21; Thu, 11 Jul 2013 12:54:35 +0200
To: John Baldwin <jhb@freebsd.org>
From: Ian FREISLICH <ianf@clue.co.za>
Subject: Re: Filesystem wedges caused by r251446
In-Reply-To: <201307091202.24493.jhb@freebsd.org>
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 <20130704082113.GJ91021@kib.kiev.ua> <E1Uudqq-0001ka-E7@clue.co.za>
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Date: Thu, 11 Jul 2013 12:54:35 +0200
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Cc: Konstantin Belousov <kostikbel@gmail.com>, freebsd-current@freebsd.org
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John Baldwin wrote:
> On Thursday, July 04, 2013 5:03:29 am Ian FREISLICH wrote:
> > Konstantin Belousov wrote:
> > > 
> > > Care to provide any useful information ?
> > > 
> > > http://www.freebsd.org/doc/en_US.ISO8859-1/books/developers-
> handbook/kerneldebug-deadlocks.html
> > 
> > Well, the system doesn't deadlock it's perfectly useable so long
> > as you don't touch the file that's wedged.  A lot of the time the
> > userland process is unkillable, but often it is killable.  How do
> > I get from from the PID to where the FS is stuck in the kernel?
> 
> Use kgdb.  'proc <pid>', then 'bt'.

So, I setup a remote kbgd session, but I still can't figure out how
to get at the information we need.

(kgdb) proc 5176
only supported for core file target

In the mean time, I'll just force it to make a core dump from ddb.
However, I can't reacreate the issue while the mirror (gmirror) is
rebuilding, so we'll have to wait for that to finish.

Ian

-- 
Ian Freislich