From owner-freebsd-hackers  Tue Nov 12 21:05:54 1996
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To: Michael Hancock <michaelh@cet.co.jp>
cc: Thomas David Rivers <ponds!rivers@dg-rtp.dg.com>,
        FreeBSD Hackers <Hackers@FreeBSD.ORG>
Subject: Re: Even more info on daily panics... 
In-reply-to: Your message of "Wed, 13 Nov 1996 13:52:14 +0900."
             <Pine.SV4.3.95.961113134357.11206A-100000@parkplace.cet.co.jp> 
From: David Greenman <dg@root.com>
Reply-To: dg@root.com
Date: Tue, 12 Nov 1996 21:04:57 -0800
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>IMHO, it's not good to speculate.  You need to confirm with absolute
>certainty that the patch is what actually fixed it.
>
>You might want to do either of the following:
>
>1) Remove the patch and see if what happens.
>
>2) Put in print statements and see if the relevent section of code ever
>gets executed.  See other #ifdef DIAGNOSTICS for examples of how to do
>this.  I think vrele() had one.

   I would also like to hear an explaination of how it is possible, after the
patch to vrele to prevent it from going negative, for a vnode with a non-zero
v_usecount can be on the freelist in the first place.

-DG

David Greenman
Core-team/Principal Architect, The FreeBSD Project