Reproducible ZFS jailed dataset panic after upgrading to latest 9-stable

[Thomas Steen Rasmussen]

Hello,

To fix the mmap vulnerability I've upgraded one of my jail hosts from:
"FreeBSD 9.1-STABLE #1: Sun Mar 17 08:48:35 UTC 2013"
to:
"FreeBSD 9.1-STABLE #3: Tue Jun 18 12:49:39 UTC 2013"

One of the jails on this machine has a jailed zfs dataset:

$ zfs get jailed gelipool/backups
NAME              PROPERTY  VALUE   SOURCE
gelipool/backups  jailed    on      local
$

After the upgrade, when I start the jail, the machine panics.

This is a remote zfs-only machine with swap on zfs, so far I have
been unable to get a proper coredump. I have access to the
console of the machine, and I have taken a couple of screenshots:

http://imgur.com/2V0PBlf and http://imgur.com/OopP9Sp

Any ideas what might have caused this ? It worked great before the
upgrade to latest 9-STABLE. This is a production server, but I am
willing to try any suggestions to get it working again.

Thanks!

Best regards,

Thomas Steen Rasmussen

ps. I have ordered a USB stick for the server which I will use to get a
coredump, but I don't know when Hetzner will get around to it.