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Date: Tue, 21 Dec 2004 18:23:46 +0000 (GMT)
From: Robert Watson <rwatson@freebsd.org>
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To: Poul-Henning Kamp <phk@phk.freebsd.dk>
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Subject: Re: Forcefully unmounting devfs...
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On Sat, 18 Dec 2004, Poul-Henning Kamp wrote:

> Brainteaser for the x-mas days:
> 
> 	What is the correct handling of busy device vnodes belonging
> 	to a devfs mountpoint which is being forcefully unmounted ?
> 
> If you think this has a simple answer, please don't bother replying. 

Being something of a traditionalist, I'd ask the question: what happens in
4.x when you forceably unmount a UFS file system out from under the device
nodes?  I'm guessing we deadfs the UFS vnodes, which results in varying
degrees of havoc depending on the device type? 

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