[libvirt] [PATCH v2] Disk- and Controller Hotplug

[Wolfgang Mauerer]

Hi,

Some time ago, Daniel P. Berrange wrote:
> On Tue, Nov 24, 2009 at 02:15:58PM +0100, Wolfgang Mauerer wrote:
>> Daniel P. Berrange wrote:
>>> On Mon, Nov 23, 2009 at 02:15:06PM +0100, Wolfgang Mauerer wrote:
>>>> Daniel P. Berrange wrote:
>>>>> Wolfgang Mauerer wrote:

>> okay, to avoid flooding the mailing list with nearly identical 
>> patches, I've put the rebased versions into a repository at 
>> git://git.kiszka.org/libvirt.git queue
> 
> I've been taking a closer look at this, and I think the final state 
> of patch series as a whole looks good. The minor issue is that the 
> intermediate patches don't compile, since they rely on compile fixes 
> at the end of the series. Rather than ask you to re-format the
> patches yet again, I'm going to just merge the patches into a smaller
> set myself.

yes, I've sacrificed individual compilability when I did the forward
porting because I the amount of time I can dedicate to this right
now is a bit restricted for various reasons. Thanks for doing the
missing cleanups!

> I've got just one question I'd like to understand before doing this.
> On the <disk> element's new <controller> element, you are allowing
> two mutually exclusive ways of specifying the controller
> 
> <disk> ... <controller name="<identifier>" bus="<number>"
> unit="<number>"/> </disk>
> 
> and
> 
> <disk> ... <controller pci_addr="<addr>" bus="<number>"
> unit="<number>"/> </disk>
> 
> I think it is going to cause unneccessary pain for applications to
> have to cope with two different ways of specifying the same
> relationship. So my intention is to remove the 'pci_addr' variant,
> since that information can easily be got directly from the separate
> top level <controller> device itself

Getting rid of pci_addr is perfectly okay. I've kept it in the current
series for setups that don't provide <controller>s, but it's supposed
to be eliminated by design. Just go ahead if you want to do this
it already now ;-)

> On a side note, once we've applied this initial series, I think we'll
>  also need to be automatically adding a <controller> element in all
> guest domains which have IDE or SCSI controllers present by default.
> This is going to also force us to hook into QEMU's 'info pci' monitor
> command to figure out their PCI address. This is long overdue though
> and needed for NIC & Disk devices added at startup too, so this is
> good motivation :-)

agreed. I can try to address this when I bring back hot-removal.

Best regards,

Wolfgang

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