[libvirt] [PATCH] pci address conflict when virtio disk with drive type address

[Eric Blake]

On 10/18/2011 03:30 AM, Xu He Jie wrote:
> When using the xml as below:

>      <memballoon model='virtio'>
>        <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>

>      </memballoon>
> </devices>
> -----------------------------
>
> Then can't statup qemu, the error message as below:
> qemu-system-x86_64: -device virtio-balloon-pci,id=balloon0,bus=pci.0,multifunction=on,addr=0x3.0x0: Device 'virtio-balloon-pci' could not be initialized

The XML doesn't match the error message (slot 4 vs. slot 3); are you 
sure you got this right?

>
> Adding check for bus type and address type. Only the address of pci type support by virtio bus.
>
> Signed-off-by: Xu He Jie<xuhj at linux.vnet.ibm.com>
> ---
>   src/conf/domain_conf.c |    8 ++++++++
>   1 files changed, 8 insertions(+), 0 deletions(-)
>
> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
> index 5959593..b8aa1a2 100644
> --- a/src/conf/domain_conf.c
> +++ b/src/conf/domain_conf.c
> @@ -2644,6 +2644,14 @@ virDomainDiskDefParseXML(virCapsPtr caps,
>       } else {
>           if (virDomainDeviceInfoParseXML(node,&def->info, flags)<  0)
>               goto error;
> +
> +        if ((def->bus ==  VIR_DOMAIN_DISK_BUS_VIRTIO)&&
> +              (def->info.type != VIR_DOMAIN_DEVICE_ADDRESS_TYPE_PCI)&&
> +              (def->info.type != VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE)) {
> +            virDomainReportError(VIR_ERR_INTERNAL_ERROR,
> +                               _("virtio only support device address type 'PCI' "));
> +            goto error;
> +        }

This feels like the wrong place for the fix.  I think the check should 
be in the qemu layer, not in the generic domain_conf, as there might be 
hypervisor drivers that support virtio on other buses.

-- 
Eric Blake   eblake at redhat.com    +1-801-349-2682
Libvirt virtualization library http://libvirt.org