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To: Bruce Evans <bde@zeta.org.au>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Mon, 15 Mar 2004 01:52:00 +1100."
             <20040315012321.X1848@gamplex.bde.org> 
Date: Sun, 14 Mar 2004 16:19:07 +0100
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cc: Don Lewis <truckman@freebsd.org>
cc: current@freebsd.org
Subject: Re: recent changes in Giant usage -> panic 
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In message <20040315012321.X1848@gamplex.bde.org>, Bruce Evans writes:

>vgone() has interesting locking problems.  It seems to be a fundamentally
>broken interface that only works if the kernel is not premptible or
>possibly if everything related to vgone() is locked by Giant.  Apparently
>the lower levels know that Giant locking is needed.

That's a fair way of putting it.  Quite a bit of the brokenness comes
from the revoke systemcall.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.