Solved: run_hotplug_scripts=0 considered unhelpful with xentools45, was: Re: guests not starting properly on 7/amd64 dom0 freshly with xen45

["S.P.Zeidler" <spz%serpens.de@localhost>]

So, to recap:

Symptom: all domU hang in kernel boot

Log:
[...]
xenbus0 at hypervisor0: Xen Virtual Bus Interface
xencons0 at hypervisor0: Xen Virtual Console Driver
xenbus: can't get state for device/suspend/event-channel (2)
xbd0 at xenbus0 id 1: Xen Virtual Block Device Interface
xennet0 at xenbus0 id 0: Xen Virtual Network Interface
xennet0: MAC address 00:16:3e:30:30:61
balloon0 at xenbus0 id 0: Xen Balloon driver
balloon0: current reservation: 8388608 KiB
xennet0: using RX copy mode
xenbus: can't get state for device/suspend/event-channel (2)
balloon0: current reservation: 2097152 pages => target: 2097152 pages
ignore shutdown request: 
xenbus: can't get state for device/suspend/event-channel (2)
<- here

and upon inspection one sees that the xbd config thread has died instead
of finishing work and reporting:

boot device: xbd0


In this situation, running xbackendd allows one to start exactly one vm,
and then further "xl create" calls will report that the hotplug setting
cannot be changed while domains are running.

This is the hint with a tent pole that the hotplug setting for xl is wrong,
and setting
run_hotplug_scripts=1 
(or commenting out the line) in /usr/pkg/etc/xen/xl.conf and a reboot
will produce a "clean" dom0 that runs domUs as intended.

For the benefit of people also upgrading from 4.2 to 4.5:

the disk specification syntax changes,
disk = [ 'phy:/dev/sd0k,0x1,w' ] # old
becomes
disk = [ '/dev/sd0k,raw,0x1,rw' ] # new, for xl

The start scripts in /etc/rc.d should be copied freshly from
/usr/pkg/share/examples/rc.d, and old xen rc.d scripts no longer present
ought to be deleted. Also /usr/pkg/etc/xen/scripts should be checked for
old scripts. Finally, there's no more xend and no more xm, use xl instead.

Thanks everybody who helped analyse this issue.

regards,
	spz
-- 
spz%serpens.de@localhost (S.P.Zeidler)