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Date: Sun, 15 Aug 2004 13:05:48 -0400 (EDT)
From: Robert Watson <rwatson@freebsd.org>
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To: =?iso-8859-1?q?Dag-Erling_Sm=F8rgrav?= <des@des.no>
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cc: Martin Blapp <mb@imp.ch>
cc: freebsd-current@freebsd.org
Subject: Re: Witness panic in pseudofs_vncache
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On Sun, 15 Aug 2004, Dag-Erling Sm=F8rgrav wrote:

> Robert Watson <rwatson@freebsd.org> writes:
> > This appears to be a bug in pseudofs due to calling vgone() while holdi=
ng
> > the pfs_vncache_mutex, as vgone() can sleep due to acquiring lockmgr
> > locks.  The fix is likely to make this looping even less efficient by
> > dropping the mutex before calling vgone() on a vnode, and then restarti=
ng.
> > I've CC'd DES because this is his baby.
>=20
> What do you think of the attached patch?=20

Has all the good and bad attributes I had expected, but hopefully will fix
the problem :-).

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org      Principal Research Scientist, McAfee Research