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Date: Mon, 2 Jan 2006 13:31:49 -0800 (PST)
From: Don Lewis <truckman@FreeBSD.org>
To: Tor.Egge@cvsup.no.freebsd.org
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Cc: gcr+freebsd-stable@tharned.org, freebsd-stable@FreeBSD.org,
	kris@obsecurity.org
Subject: Re: Recurring problem: processes block accessing UFS file system
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On 26 Nov, Tor Egge wrote:
> 
>> Thanks Kris, these are exactly the clues I needed.  Since the deadlock 
>> during a snapshot is fairly easy to reproduce, I did so and collected this 
>> information below.  "alltrace" didn't work as I expected (didn't produce a 
>> trace), so I traced each pid associated with a locked vnode separately.
> 
> The vnode syncing loop in ffs_sync() has some problems:

There is also a MNT_VNODE_FOREACH() loop in ffs_snapshot().