system stalls when wallclock/TOD nudged

[Colin Percival]

Hi all,

I'm seeing a weird bug here, and I'm wondering if anyone else has experienced
this and/or has any clue how to fix it.

During the boot process, in the middle of running rc.d scripts, my FreeBSD/Xen
instance stalls.  It does nothing until I send a shutdown signal, at which point
> [XEN] hypervisor wallclock nudged; nudging TOD.
and a couple buffered lines of rc.d script output are printed.  From there the
rc.shutdown script starts running, but it too stalls after a short time; then I
see
> [XEN] hypervisor wallclock nudged; nudging TOD.
> Nov 19 14:08:33 init: timeout expired for /bin/sh on /etc/rc.shutdown: Interrupted system call; going to single user mode
printed, suggesting that the shutdown watchdog timer at least managed to not get
stuck even though everything else did.

Any ideas?

-- 
Colin Percival
Security Officer, FreeBSD | freebsd.org | The power to serve
Founder / author, Tarsnap | tarsnap.com | Online backups for the truly paranoid