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From: Andrey Simonenko <simon@comsys.ntu-kpi.kiev.ua>
To: Sebastien <sebastien.bourdeauducq@gmail.com>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Filesystem access from a KLD causes "vrele: negative ref cnt"
	panic
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On Tue, Sep 20, 2005 at 07:49:53PM +0200, Sebastien wrote:
> 
> I have a random panic "vrele: negative ref cnt" when I shutdown the system. Am 
> I double-freeing something in my code ? The fact that the panic is caused 
> randomly suggests there is a synchronization problem - but the above code is 
> always running under the protection of the Giant mutex.

[ please don't write such long lines ]

Should not rootvnode get reference, when fd_rdir or fd_cdir
begins to point to it?  Try to VREF() it.  Which vnode gets negative
reference counter?