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Date: Sun, 15 Jun 2003 08:50:58 -0700
From: David Schultz <das@FreeBSD.ORG>
To: Tom Alsberg <alsbergt@cs.huji.ac.il>,
	FreeBSD Hackers List <freebsd-hackers@FreeBSD.ORG>
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Mail-Followup-To: Tom Alsberg <alsbergt@cs.huji.ac.il>,
	FreeBSD Hackers List <freebsd-hackers@freebsd.org>
References: <20030615112920.GA39687@cs.huji.ac.il>
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Subject: Re: (bug?) panic in union filesystem - file/.
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On Sun, Jun 15, 2003, Tom Alsberg wrote:
> I recently stumbled upon a crash in the union filesystem.  It seems
> that when trying to stat "<file>/." where file is a regular
> (non-directory) file in a union mounted filesystem, the system will
> panic.
> 
> I first noticed this as an effect of zsh (Z shell)'s tab completion,
> which after I checked, tries to lstat "<file>/." if there are no other
> completions and the file exists, to see if it is a directory with
> other files in it which it should try to complete (I do not know why
> they chose to do it this way).
> 
> It seems like a bug in the union filesystem to me.  I can reproduce it
> on both 4.8-STABLE and 5.1-CURRENT.

This problem is on my TODO list, but it may take me a while before
I have a chance to look at it.  It would help me to keep track of
it if you could file what you just said (verbatim, even) as a
followup to kern/53004, though.  Thanks for investigating the
issue!