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Date: Thu, 24 Jul 2014 09:36:52 -0400
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Subject: Re: NFS DEADLKRES panic with getfsstat() on unresponsive mount
From: Ryan Stone <rysto32@gmail.com>
To: Bryan Drewery <bdrewery@freebsd.org>
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On Tue, Jul 22, 2014 at 5:15 PM, Bryan Drewery <bdrewery@freebsd.org> wrote:
> I had an NFS server go offline for about an hour and had a client panic in
> deadlkres after a 'zfs list -o mounted' ran which called getfsstat(2). It
> seems reasonable that this could be a false-positive. Is deadlkres known to
> have acceptable false-positives? If so, is there a way to mark this one to
> not cause a panic?
>
> This was r268621.

There is a list of "blessed" sx lock names in sys/kern/kern_clock.c.
deadlkres will ignore any threads sleeping with one of those wmesgs.