booting oneiric in xen hvm domU

Stefan Bader stefan.bader at
Wed Sep 21 21:53:10 UTC 2011

On 21.09.2011 23:32, Mark Dokter wrote:
> On 9/21/11 2:19 PM, Stefan Bader wrote:
>> On 21.09.2011 12:56, Mark Dokter wrote:
>>> On 09/20/2011 09:46 AM, Stefan Bader wrote:
>>>> That sort of is normal and depends on the guest. Except the virtual kernel, all
>>>> other kernels have the blockfront and netfront drivers only compiled as a
>>>> module. If one wants to use them, then those need to go into the list of early
>>>> loaded modules. Or as with the argument, xen gets told to keep the emulated disk
>>>> and network devices.
>>>> But it would be worth documenting this at least in the release notes, I guess.
>>> How early is early ? I guess the modules are in the initrd, since I can
>>> drop to a shell and load them. But this doesn't reveal disks/nics.
>> In theory I would expect things to work when either loaded from the shell or the
>> required module names being placed into /etc/initramfs-tools/modules.
>> However when I tried now, it does not seem to work. I really think it had been
>> working, but that may have been back with xen-4.1.0. Moving to 4.1.1 seems to
>> have bought a few undesirable "features"... :/
> I just checked /boot/config-3.0.0-11-server and I guess the combination
> of CONFIG_XEN_PLATFORM_PCI=m and xen-platform-pci.ko not being in the
> initrd cause the devices to not appear. I come to this conclusion since
> installing with the xen_emul_unplug=unnecessary (or 'never' does
> effectively the same thing in this situation) and then changing to pv
> drivers by putting xen-platform-pci, xen-blkfront and xen-netfront in
> /etc/initramfs-tools/modules works (mostly, but thats a different story...).
The feedback there was to my understanding one should never get pv drives. Which
sounds odd. Especially when the default is: oh you have pci platform _and_ pv
drivers, then I throw away the emulated devices. In that case you would want the
pv devices to be used. And the modules are in the initrd for me. It is the fact
that both are compiled (module or not does not matter).
>> -Stefan
>>>> Note, that emulated net seems still have some issues under load the last time I
>>>> looked.
> So the e1000 model works better? (read your inquiry about that on
> xen-devel *g*)

It does, as a quick workaround. And disabling the event based interrupts makes
the default 8139cp work as expected again. :)

> cheers,
> Mark

More information about the ubuntu-server mailing list